Like seeing an old friend--when this machine last wobbulated, I was beginning a basic electricity course at Lowry AFB en route to becoming an aircraft weapons mechanic. Much later, I was to learn that wobbulated signals centered on 4300 MHz are the basis for commercial aircraft radio altimeters. Somewhere in between, I came to recognize the quarter-turn fasteners on the top of the box as authentic Dzus fasteners, the original quick-release fasteners used on the DC-3. I still have a screwdriver I cut down in 1965 to fit under DC-3 cowl flaps and unlock Dzus fasteners in the engine accessory cowling. Next, I will watch your video on VTVM restoration and learn what I might need before I dig my old Heathkit IM-28 out of the closet. Thanks for the motivation.
I know this is a few years back Paul, but what a piece of kit!.You can see it was purpose designed and built especially for the job it did.Which is slightly different to the Marconi R1155 receiver that I am trying hard to fully restore.That was needed quickly, but hey it did an excellent job.Which is a tribute to the electronic guys who designed it.Just absolutely love this old equipment.If only I had purchased more of it in the early days, when it could hardly be given away.I could sell it off now and be better off than I am now.Brilliant Channel.Going to increase my Patrion subs very soon.Thanks for the excellent channel Paul.And the knowledge that you impart.It is appreciated by so many of us.
You might be surprised and find all the caps are still good. I have a lot of 40-60's military test equipment and radios and don't think I have ever changed one yet. I'm always amazed at the quality and durability of milspec capacitors. Many are hermetically sealed. Might be worth unhooking them and testing them for leakage. Thats what I do and haven't changed one yet. Will be nice to see this back up and running. I love old military gear. Mike
Great find Mr Carlson. I bet you smiled when you took off the bottom panel. There can't be too many manuals for that unit around anymore. I have an old 50's military FM transceiver (uses 1U4's etc). Was happy to find a schematic printed on a silk material folded away inside. Looking forward to another one of your excellent restorations !
+Todd Anonymous You Bet! That was a great surprise! One day I will build a portable radio project with those 1 Volt filament tubes. I have quite a few.
Such a well built, sturdy apparatus. Just goes to show the difference between long lasting, military engineering and 'built-in obsolescence' consumer electronics!
Very nice demonstration Paul; I was sold a military breadboard that is built like a tank "heavy". All the potentiometers are wirewound, full of features and a multiple power supply giving unlimited approach to designing. Each section pulls out for easy servicing and I was lucky to get the manual with it. I love military stuff, well built to last.
+Mr Carlson's Lab Let's not forget about soldiers that actually had to carry this boat anchor in the field. Thing probably weights more than a box of grenades, and with box of grenades you can at least defend yourself! ;) Unless you consider throwing this from the roof to the enemy's head as alternative application.
Thanks for the prompt reply to my comment. I had a No 11 Australian army radio R/T set (it too weighed a lot) that not only was tropicalised for work in the Pacific zone but, like your wobbulator, had the circuit diagram on the inside of the removable base. A very useful addition.
Hernia in a box! The build quality on this old gear is just incredible! I'd clip some notches in the cap cans, pry them open, stuff new caps inside, epoxy around the bases, crimp them back closed, & use a hose clamp with wax paper to clamp it while the epoxy dries. Use the wax paper or Saran wrap. You may not want hose clamps glued on there permanently. I have some USN VTVMs, and a thermal volt meter. The schematics are pasted inside ALL of them.
I repair Ampeg Tube Amplifiers and they too paste a copy of the correct Rev schematic inside the cover. I agree 5 Stars all the way !!! Very nice piece of gear you've shown us Paul - thank you.
back in the 80's I had a wobbulator in my workbench. If I remember well, the brand was "Crescent" and instead of a rotary motor for sweeping the L.O., it had one half of the variable capacitor mounted on a huge moving coil (just like a speaker) whereas the other half of the cap was coupled to the center frequency front knob mechanism. If I remember well, that unit went up to 450MHz or so, and I was amazed by the ingenuity behind its design. Cheers from Buenos Aires Paul !!
Beauty and a full schematic as well... that is unheard of these days. I am almost always impressed by this older hardware. Not only is the build quality and attention to detail usually most excellent the manuals read like textbooks. I've learned so much from perusing old test gear manuals -- especially older high-frequency RF gear.
brilliant bit of old kit ...over here in the UK lots of old ex army surplus are always turning up on ebay and at second hand stores and junk shops ...sadly loads are scrapped as the average person to come across them just think there scrap .....keep up your good work ☺
As far as i can recall, it was quite common for Radio- and TV-sets from the tube era to have schematics sheets in every single unit; that way a repair workshop wouldn't need to have a bunch of different ones in stock on the off-chance that they some day *MIGHT* have to repair a less common unit type. These schematics were in part what led me down the road to become a hobby electronician. :) As always, a very interesting video, Mr. C! Keep up the good work. Greetings from Denmark.
Wow, very interesting teardown and explanation of this unit Paul. This time I will say it looks like it was built "FOR" a tank.. I have a big bag of those plug in style NOS capacitors. As we know as old as they are they are only conversation pieces. That manual sweep circuit is interesting. Wonder how they are keeping noise to a minimum there. Will enjoy seeing you get this back up to speck. Thanks for another great tech tip Paul. Thumbs up!
The capacitor setup in the sweep circuit reminds me of the scanner in Hammond organs. They use that in tandem with some filters to create a phase shifter. They used this to create vibrato in the tone.
What a fantastic piece of equipment! I was ready to see a (the usual) massive entanglement of wires and components under the bottom cover, pleasant surprise instead! Thanks for the video!
Ha ha ha, he said Wobbulator... Hu hu, hu hu... The way the military built things was just astounding! I'll bet the reason they used a mechanical sweep was for pure reliability in the field. Awesome find!
Hi there Mr Carlsson! Will there be a restoration video of this unit? Because I am really looking forward to it. Aldo, I love your videos, keep 'em coming! 😊👍
Newer technologies may have more bells and whistles than the older gear, but the quality and engineering excellence of older technology is amazing! They really built things to last back in the day. Good luck trying to find that now in our current age of planned obsolesce.
Hi Paul, Wobbulator. NU metal, dzus fastners. Terminology I haven't heard in years. Great video on an old piece of Mil Spec test gear. The wobbulator was used many years ago by Eico in ther sweep generator. Eico however used the movement of the speaker coils inductance to change the sweep rate. Keep up the great work Paul. I thoroughly enjoy your Tech Tip videos. Don
+Donald J. Mangold Hi Don, old64goat, down the list mention a similar unit with a speaker coil design. Heathkit used a saturable reactor to the job, my Singer metrics spectrum analyzer uses the same. Thanks for your kind words!
I found one of these in my fathers stuff when he past away, I did not get the time to play with yet but il try to post a picture wen I dig it back out. Its a more portable version as it it smaller but still very hefty. nice to finally see a glimpse of what it can possibly do. Nice job.
Fascinating piece of equipment. Love your videos on vintage electronics. Learning a lot that will help me in restoration of my old Geiger counters. Thanks!
Another awesome video, and an extremely interesting piece of history. I think your lab, btw, probably has more broadcasting, processing and analyzing power than most countries entire intelligence departments. Well done!
I would re-stuff those caps, to keep something like this as close to original as possible. Hell, even re-stuff all the caps may be a good idea :) Nice video Paul. I love to see how this older tech was made a the sheer craftsmanship that has been put into such a unit!
And here I thought dynamotors were a clever way to bump DC to high voltage DC! That motorized sweep generator system is something I have never heard of before, that's really cool, almost going back to electro mechanical television!
The BBC Radiophonic Workshop used multiple instances of these back in the 60s and 70s as audio sources for sound effects and theme music for TV programs.
We used a similar one to tune vehicle tracking system front-end receiver filters back in 1988 in South Africa when they were using a 'fox hunt' triangulation system (4 antennas on a square ground-plane on police squad cars) that would rebroadcast two local beacons on the tracking frequency that would allow for a LORAN by proxy location system that was good to a few hundred meters and did not need expensive and easily shielded GPS of the day. The systems were hidden into vehicle upholstery and seats and had no connection besides a wire to charge the small backup cell. I think they were activated from the beacon signals by the tracking company and the police could home in on them quickly.
I have several Wobbulators taken from APN1 radio altimeters. They have a voice coil driving a dome, much like a compression tweeter that is near silver plated areas on a porcelain plate. The areas tied to a tuned line with a couple acorn tubes that form an oscillator in the UHF range. The Wobbulator coil was driven by an output transformer driven by a tube. They appear to have Alinco magnets.
Excellent video Paul. I think you have your "Teardown" format just right. This is another instance where I appreciate your high quality video and good lighting, particularly when looking at the schematic. The Wobbulator itself is a fascinating piece of equipment; I love the quality of workmanship and general serviceability of military grade gear from that era. Overall, a winner! Thanks. Edit: Did I see a couple of Sprague "Vitamin Q" capacitors on the bottom chassis RHS near the potentiometers? These are gold to the tube audio folks. I have more than a passing connection to this type/grade of equipment. My Dad was a Cdn Navy Radar Tech in WWII and my first lessons in electronics were from him. Looking forward to see this old school high tech piece of gear restored to your exacting standards.
+Shaun Merrigan Thanks for your input Shaun! Ya know, I didn't pay attention to the brand, they very well may be the old Vitamin Q type. When I get into the resto, I will take note.
Paul, I've restored a few Mil-Std devices; one concern: finding carbon comp resistors of equivalent tolerance and value (without going down the "metal film" trail). One tip, Gudebrod nylon lacing cord should be used when having to replace wiring contained withing the breakouts/bundles. Thanks for a trip back to our formerly redundant past!
Always look forward to your rebuild videos of old gear (test gear a plus). i look forward to the full rebuild video in the future. it was a nice touch to find the schematic under the bottom panel. they sure don't make things like that anymore.
LOL... I started saying I need to use the wobbulator when I wanted to borrow the Aeroflex. Very fun! We got several Wobbulators but that is the only one that we own that is P25 certified by the feds.
Wow, that test equipment is in pristine condition. Understood that the caps will need to be replaced, but its so clean, you may want to just plug it in right now! Once you get it going, I will bring by my two BC 1004's for alignment! We both will get a good workout from lugging all those boat anchors
The best I assume the unit was built by either the USA or Canada right it was very interesting to say the least pretty well made to again say the least thank you paul
Paul i can't help but be impressed with editing and even manner approach to these educational videos do you ever have out takes or bloopers just wandering I think with your approach to repairs has something for everone and important stuff you go over more than once in the videos nice complete!!
18:10 It's a military field unit and a highly specialized mission-critical piece of equipment; of course it's going to have the schematic on the bottom chassis plate. A field tech can't be expected to carry around schematics for every piece of gear he could possibly encounter and DARPAnet didn't exist yet. This wasn't uncommon in civilian gear either. I've seen a Motorola jukebox schematic on a chassis plate like that. (It was just the amplifier chassis, but I'm sure the disk changer mechanism had its schematic in the case as well.)
Vintage military stuff is always so fascinating and the thing looks VERY User Serviceable too, the alan keys and extra fuses under the control plate was a nice touch. Modern electronics just dont compare
I look forward to your rebuilding of this one. I am amazed at how good the condition is. BTW the diagram on the bottom cover was normal for this time period for alot of the Air Force test gear. It was there just in case the T.O. (technical order) was not around.
That thing looked like it would have survived a nuclear blast and I bet that really was one of the design criteria. Truly amazing the craftsmen ship that went into that unit. I wonder what it actually cost the government to make it back in the 1950s.
Is a piece of equipment like that still useful for today? Is it worth fixing and calibrating? I love his videos of old equipment and restoring them. He reminds me of my dad when he would fix his stuff.
It's funny, I have used a wobbulator, but it was a completely different thing. We used it to calibrate the sensors on rotating equipment that measured vibration. It had a rotating disk that was flat but eccentric. Imagine a record player with a spacer under one side. As the record turns you get an upwards movement and hen a downwards movement. We would measure this with a dial indicator, and we could calibrate our probes to this movement. Literately measuring how much it wobbled....
What advantage is the motor for the sweep generator? Why wouldn't they just do it with an electronic oscillator? Very good explanations. I'm addicted to thermionic emissions. Much of my Ham station is tube gear as well. You are much younger than me albeit much more educated. Why did you take an interest in tube gear? Thanks very much for the video's. I was never able to finish my EE. Your video's help fill in the gaps.
I think the problem is the technology to do the sweep back then was much more limited. Keep in mind that you need a linear relationship between the frequency and the sweep voltage, or else your frequency scale on the scope is going to look strange. You also need to sweep a very wide frequency range.
Most oscilloscopes have a swept horizontal time base, so how would this differ from a regular oscilloscope? I have been around old test equipment for a while now, and this the first time I have seen or heard of such a unit. While I have seen external sweep generators before, I never had a need to use one. The mechanical driven sweep circuit sounds similar to the electronic version of a Leslie speaker in which they used a motor to turn the plates of a continuous rotating variable capacitor and this is what caused the sound to shift from speaker to speaker, creating a stereo rotating speaker effect.
When I worked outside plant for the phone company as a young man, the saying then was that if the test meter wasn't heavy already, then they'd put it in a heavy box to make up for it.
That schematic looks like it was drawn by the same guy who drew up Leo Fender's schematics..... Very organized, logical, and fairly easy to follow. Those were the days......
Hi again Mr. Carlson. Would you mind sharing an high resolution image of the schematic for your wobbulator with a link for your subscribers as a reference for those who may also be restoring this type of equipment or just have a general interest in studying electronics? I had to look around quite a bit to find any documentation for the wobbulator online and I think it would be helpful if we subscribers could find it on your channel. Thanks for the great videos and keep up the good work!
+uomo d'onore Hi, I snapped a few pix of the wobbulator schematic, but haven't even uploaded them yet. I will consider a file sharing account in the future.
That is a neat piece of test gear, oh the wobbulator that reminds me of my very first sweep generator, it was a very old Hickok and it used a regular speaker without the cone, it had a metal plate and was something like a vibrating capacitor, depending on how strong the AC voltage was applied to the "voice coil" determined the sweep width. It just used a low 60 cps voltage on the "voice coil" BTW, I never liked saying hertz, on these old things I like the good old CPS...LOL
A Radio Collector Mate gave me a 1970 Nordmende Wobbulator for free. All the Tubes were pulled and for now it's only smoking, when I got space again to work on it I will try to restore it... Thank's for the Explaination!
Now that the labs are being moved, I will come across it again. It's behind about 10000 pounds of equipment in storage. It will have it's day on the bench :^)
Carl picks up a Collins R390A for a restoration process, alignment and replacement of components ... It would be very interesting to see his talent when dealing with a radio receiver such. A radio show receiver in the hands of a true artist of electronics.
This looks like a Jack Davis or, more like Wallace Wood 1954 mad magazine cartoon. That observation aside, this is another of Mr Carlson's great example of the timeless quality equipment this country built..at one time.....
You mentioned the calibration dates, so Heres a tip on that. The reason for 6 months is the quality of the equipment didn't stay in calibration for much more than 6 months, so its reliability was in question. However if its cal. dates were say 3 years instead, then it could be a more reliable piece of test equipment. Signifying the calibration would tend to to be more dependable (Stay in Calibration for a longer period of time.)
![Delco High Performance Radio Receiver! [Repair]](/img/n.gif)
Like seeing an old friend--when this machine last wobbulated, I was beginning a basic electricity course at Lowry AFB en route to becoming an aircraft weapons mechanic. Much later, I was to learn that wobbulated signals centered on 4300 MHz are the basis for commercial aircraft radio altimeters. Somewhere in between, I came to recognize the quarter-turn fasteners on the top of the box as authentic Dzus fasteners, the original quick-release fasteners used on the DC-3. I still have a screwdriver I cut down in 1965 to fit under DC-3 cowl flaps and unlock Dzus fasteners in the engine accessory cowling. Next, I will watch your video on VTVM restoration and learn what I might need before I dig my old Heathkit IM-28 out of the closet. Thanks for the motivation.
+Hopelessand Forlorn
Thanks for taking the time to write. Great story! Glad your enjoying the video's.
Hopelessand Forlorn 6
Weebles used this to fix their TVs and Radios
I think I learn more from your videos on this older tech than I do from some review of the latest manufacturer supplied test gear. Thank you.
I know this is a few years back Paul, but what a piece of kit!.You can see it was purpose designed and built especially for the job it did.Which is slightly different to the Marconi R1155 receiver that I am trying hard to fully restore.That was needed quickly, but hey it did an excellent job.Which is a tribute to the electronic guys who designed it.Just absolutely love this old equipment.If only I had purchased more of it in the early days, when it could hardly be given away.I could sell it off now and be better off than I am now.Brilliant Channel.Going to increase my Patrion subs very soon.Thanks for the excellent channel Paul.And the knowledge that you impart.It is appreciated by so many of us.
You might be surprised and find all the caps are still good. I have a lot of 40-60's military test equipment and radios and don't think I have ever changed one yet. I'm always amazed at the quality and durability of milspec capacitors. Many are hermetically sealed. Might be worth unhooking them and testing them for leakage. Thats what I do and haven't changed one yet. Will be nice to see this back up and running. I love old military gear.
Mike
+MikesRadioRepair
Thanks for your comment Mike!
This is a capacitor testing channel, I'm pretty confident they will be carefully checked.
I am just a hobby tech, love all of your videos and you teach a lot to all who view, keep it up, whish I had an instructor in school like you.Thanks
Great find Mr Carlson. I bet you smiled when you took off the bottom panel. There can't be too many manuals for that unit around anymore. I have an old 50's military FM transceiver (uses 1U4's etc). Was happy to find a schematic printed on a silk material folded away inside. Looking forward to another one of your excellent restorations !
+Todd Anonymous
You Bet! That was a great surprise! One day I will build a portable radio project with those 1 Volt filament tubes. I have quite a few.
+Mr Carlson's Lab looking fowar to that too. (big trasmitter pls)
Such a well built, sturdy apparatus. Just goes to show the difference between long lasting, military engineering and 'built-in obsolescence' consumer electronics!
Very nice demonstration Paul; I was sold a military breadboard that is built like a tank "heavy". All the potentiometers are wirewound, full of features and a multiple power supply giving unlimited approach to designing. Each section pulls out for easy servicing and I was lucky to get the manual with it. I love military stuff, well built to last.
+John Cunningham
Thanks for your comment John!
Quite a simple circuit really but built like a battle ship. Can you imagine building to this standard today, the cost would be un thinkable.
+Michael Beeny "An elephant is just a mouse built to government specification." - Robert Heinlein's Lazarus Long
+Michael Beeny
I agree! They could recycle this and build a ship out of it.
+Mr Carlson's Lab Let's not forget about soldiers that actually had to carry this boat anchor in the field. Thing probably weights more than a box of grenades, and with box of grenades you can at least defend yourself! ;) Unless you consider throwing this from the roof to the enemy's head as alternative application.
Definitely not a front line piece of gear more likely used at an airfield repair facility, rear area, or aboard a ship.
+Michael Beeny Kinda like a sixteen cylinder Caddilac!
Thanks for the prompt reply to my comment. I had a No 11 Australian army radio R/T set (it too weighed a lot) that not only was tropicalised for work in the Pacific zone but, like your wobbulator, had the circuit diagram on the inside of the removable base. A very useful addition.
+DAVET38
Thanks for your comment Dave!
Hernia in a box! The build quality on this old gear is just incredible! I'd clip some notches in the cap cans, pry them open, stuff new caps inside, epoxy around the bases, crimp them back closed, & use a hose clamp with wax paper to clamp it while the epoxy dries. Use the wax paper or Saran wrap. You may not want hose clamps glued on there permanently. I have some USN VTVMs, and a thermal volt meter. The schematics are pasted inside ALL of them.
+Seth B
That sounds like a nice clean way to rebuild those caps. Thanks for your input!
I repair Ampeg Tube Amplifiers and they too paste a copy of the correct Rev schematic inside the cover. I agree 5 Stars all the way !!! Very nice piece of gear you've shown us Paul - thank you.
+Ron C
Thanks Ron!
Every thin I build has a copy of my he schematic inside the unit with a parts map
You are the Bob Ross of electrical engineering. I love it. Ty.
Thanks for your kind comment Casey!
You explained things excellently, to someone who didn't understand the components description thanks
back in the 80's I had a wobbulator in my workbench. If I remember well, the brand was "Crescent" and instead of a rotary motor for sweeping the L.O., it had one half of the variable capacitor mounted on a huge moving coil (just like a speaker) whereas the other half of the cap was coupled to the center frequency front knob mechanism. If I remember well, that unit went up to 450MHz or so, and I was amazed by the ingenuity behind its design. Cheers from Buenos Aires Paul !!
Thanks for your comment Marcelo!
Again another wonderful lecture. Congratulations, Mr Carlson!
Another great video, those gray boxes have nice surprises in them and sometime not so great. Looking forward to the rebuild. Keep them comming. Greg
+Gregory West
Thanks Greg!
Beauty and a full schematic as well... that is unheard of these days. I am almost always impressed by this older hardware. Not only is the build quality and attention to detail usually most excellent the manuals read like textbooks. I've learned so much from perusing old test gear manuals -- especially older high-frequency RF gear.
+Justin “J” Lynn
You bet Justin! That's where you will find the answers, you are on the right track.
That and here. "Woah. You're a cool teacher, Mr Carlson!" :D
Thanks Justin! I appreciate the kind comment.
brilliant bit of old kit ...over here in the UK lots of old ex army surplus are always turning up on ebay and at second hand stores and junk shops ...sadly loads are scrapped as the average person to come across them just think there scrap .....keep up your good work ☺
+retro80s
Thanks!
As far as i can recall, it was quite common for Radio- and TV-sets from the tube era to have schematics sheets in every single unit; that way a repair workshop wouldn't need to have a bunch of different ones in stock on the off-chance that they some day *MIGHT* have to repair a less common unit type. These schematics were in part what led me down the road to become a hobby electronician. :)
As always, a very interesting video, Mr. C! Keep up the good work.
Greetings from Denmark.
Wow, very interesting teardown and explanation of this unit Paul. This time I will say it looks like it was built "FOR" a tank.. I have a big bag of those plug in style NOS capacitors. As we know as old as they are they are only conversation pieces. That manual sweep circuit is interesting. Wonder how they are keeping noise to a minimum there. Will enjoy seeing you get this back up to speck. Thanks for another great tech tip Paul. Thumbs up!
+The Radio Shop
Glad you enjoyed Buddy! Looking forward to your next video :^)
Looking forward to seeing the finished restoration. I have never seen one of these and love the mechanics used to get the job done.
+hankus253
Thanks Hank!
The capacitor setup in the sweep circuit reminds me of the scanner in Hammond organs. They use that in tandem with some filters to create a phase shifter. They used this to create vibrato in the tone.
What a fantastic piece of equipment! I was ready to see a (the usual) massive entanglement of wires and components under the bottom cover, pleasant surprise instead! Thanks for the video!
+Tony T.
They did a nice clean assembly job, that's for sure! Glad you enjoyed Tony.
Mrs C comes into the lab, hears there's something vibrating in the wobulator. You must have some strange dinner conversations.
Ha ha ha, he said Wobbulator... Hu hu, hu hu...
The way the military built things was just astounding!
I'll bet the reason they used a mechanical sweep was for pure reliability in the field.
Awesome find!
Hi there Mr Carlsson! Will there be a restoration video of this unit? Because I am really looking forward to it. Aldo, I love your videos, keep 'em coming! 😊👍
Newer technologies may have more bells and whistles than the older gear, but the quality and engineering excellence of older technology is amazing! They really built things to last back in the day. Good luck trying to find that now in our current age of planned obsolesce.
+uomo d'onore
I do agree! Thanks for your comment!
Hi Paul,
Wobbulator. NU metal, dzus fastners. Terminology I haven't heard in years. Great video on an old piece of Mil Spec test gear. The wobbulator was used many years ago by Eico in ther sweep generator. Eico however used the movement of the speaker coils inductance to change the sweep rate. Keep up the great work Paul. I thoroughly enjoy your Tech Tip videos.
Don
+Donald J. Mangold
Hi Don, old64goat, down the list mention a similar unit with a speaker coil design. Heathkit used a saturable reactor to the job, my Singer metrics spectrum analyzer uses the same. Thanks for your kind words!
" Mu " metal
Fun stuff! Can't wait to see you restore it and fire it up!
+PelDaddy
Me Too! Thanks for your comment.
I found one of these in my fathers stuff when he past away, I did not get the time to play with yet but il try to post a picture wen I dig it back out. Its a more portable version as it it smaller but still very hefty. nice to finally see a glimpse of what it can possibly do. Nice job.
Thank you for another excellent video, it is always fascinating to see how beautifully made old test equipment was.
Fascinating piece of equipment. Love your videos on vintage electronics. Learning a lot that will help me in restoration of my old Geiger counters. Thanks!
+Geiger Counter Virtual Museum
Your welcome!
So very interesting, my dad used to talk about Wobulators and I always thought he was kidding.
What a cliffhanger, I searched like a crazy for that restoration video :p
Another awesome video, and an extremely interesting piece of history. I think your lab, btw, probably has more broadcasting, processing and analyzing power than most countries entire intelligence departments. Well done!
+jrdubois112277
Thanks for your kind words!
Huge creative inspiration im learning alot while also learning hands on chemistry thank you dont stop posting
So cool Paul you refurb older test equipment! Another Very Cool Video!!! Thanks
+llsdigitek
Your welcome!
I would re-stuff those caps, to keep something like this as close to original as possible. Hell, even re-stuff all the caps may be a good idea :) Nice video Paul. I love to see how this older tech was made a the sheer craftsmanship that has been put into such a unit!
+hydrolisk1792
Thanks for your input!
Very interesting, some great craftsmanship there. Looking forward to the restoration.
+Chuck Legg
Thanks Chuck!
You made me want to sign up for you tube, thank you, I have something like your wobbulator. keep up the good work.
Hey, great to read! Welcome aboard! :^)
And here I thought dynamotors were a clever way to bump DC to high voltage DC! That motorized sweep generator system is something I have never heard of before, that's really cool, almost going back to electro mechanical television!
The BBC Radiophonic Workshop used multiple instances of these back in the 60s and 70s as audio sources for sound effects and theme music for TV programs.
We used a similar one to tune vehicle tracking system front-end receiver filters back in 1988 in South Africa when they were using a 'fox hunt' triangulation system (4 antennas on a square ground-plane on police squad cars) that would rebroadcast two local beacons on the tracking frequency that would allow for a LORAN by proxy location system that was good to a few hundred meters and did not need expensive and easily shielded GPS of the day. The systems were hidden into vehicle upholstery and seats and had no connection besides a wire to charge the small backup cell. I think they were activated from the beacon signals by the tracking company and the police could home in on them quickly.
Excellent. Can't wait for the restoration video. Hell of a piece of equipment.
+InTheNameOfJustice
Thanks!
I have several Wobbulators taken from APN1 radio altimeters. They have a voice coil driving a dome, much like a compression tweeter that is near silver plated areas on a porcelain plate. The areas tied to a tuned line with a couple acorn tubes that form an oscillator in the UHF range. The Wobbulator coil was driven by an output transformer driven by a tube. They appear to have Alinco magnets.
Excellent video Paul. I think you have your "Teardown" format just right. This is another instance where I appreciate your high quality video and good lighting, particularly when looking at the schematic. The Wobbulator itself is a fascinating piece of equipment; I love the quality of workmanship and general serviceability of military grade gear from that era. Overall, a winner! Thanks.
Edit: Did I see a couple of Sprague "Vitamin Q" capacitors on the bottom chassis RHS near the potentiometers? These are gold to the tube audio folks.
I have more than a passing connection to this type/grade of equipment. My Dad was a Cdn Navy Radar Tech in WWII and my first lessons in electronics were from him. Looking forward to see this old school high tech piece of gear restored to your exacting standards.
+Shaun Merrigan
Thanks for your input Shaun! Ya know, I didn't pay attention to the brand, they very well may be the old Vitamin Q type. When I get into the resto, I will take note.
Enjoyed the video, now patiently waiting for the restoration video ;)
Thank you very much Paul and looking for the restoration video.
+esmaeil nam
Thanks Esmaeil!
Paul, I've restored a few Mil-Std devices; one concern: finding carbon comp resistors of equivalent tolerance and value (without going down the "metal film" trail). One tip, Gudebrod nylon lacing cord should be used when having to replace wiring contained withing the breakouts/bundles. Thanks for a trip back to our formerly redundant past!
+AMStationEngineer
Glad you enjoyed!
Your logical approach gives me a much needed brain alignment.
Always look forward to your rebuild videos of old gear (test gear a plus). i look forward to the full rebuild video in the future. it was a nice touch to find the schematic under the bottom panel. they sure don't make things like that anymore.
+preludelinux
Thanks for your kind words!
LOL... I started saying I need to use the wobbulator when I wanted to borrow the Aeroflex. Very fun! We got several Wobbulators but that is the only one that we own that is P25 certified by the feds.
Would love to see the restoration of the wobbulator and a video of it in action.:)
Great vids keep up the great work!
super old test gear and excellent video Paul. Can't wait until you rebuild it. Take care!
+TRXBench
Thanks Peter! Look forward to your next Video as well.
The older gear has the best parts thumbs up
Wow, that test equipment is in pristine condition. Understood that the caps will need to be replaced, but its so clean, you may want to just plug it in right now! Once you get it going, I will bring by my two BC 1004's for alignment! We both will get a good workout from lugging all those boat anchors
+Scott Johnston
They sure are heavy! Thanks for your comment Scott!
The best I assume the unit was built by either the USA or Canada right it was very interesting to say the least pretty well made to again say the least thank you paul
Paul i can't help but be impressed with editing and even manner approach to these educational videos do you ever have out takes or bloopers just wandering
I think with your approach to repairs has something for everone and important stuff you go over more than once in the videos nice complete!!
18:10 It's a military field unit and a highly specialized mission-critical piece of equipment; of course it's going to have the schematic on the bottom chassis plate. A field tech can't be expected to carry around schematics for every piece of gear he could possibly encounter and DARPAnet didn't exist yet.
This wasn't uncommon in civilian gear either. I've seen a Motorola jukebox schematic on a chassis plate like that. (It was just the amplifier chassis, but I'm sure the disk changer mechanism had its schematic in the case as well.)
Cool old piece Paul. Looking forward to the restoration. 73, Bill KC5SB
+rollerbald
Thanks Bill!
Vintage military stuff is always so fascinating and the thing looks VERY User Serviceable too, the alan keys and extra fuses under the control plate was a nice touch. Modern electronics just dont compare
+Nexfero
I agree.
That's a cool unit, looks to be really well built. Thanks for sharing!
Built like a tank, and weighs just as much.
I look forward to your rebuilding of this one. I am amazed at how good the condition is. BTW the diagram on the bottom cover was normal for this time period for alot of the Air Force test gear. It was there just in case the T.O. (technical order) was not around.
Thanks for your comment Richard!
Looking forward to that rebuild, that is quite an interesting piece of equipment!
+Tom k2bew
Thanks Tom!
That thing looked like it would have survived a nuclear blast and I bet that really was one of the design criteria. Truly amazing the craftsmen ship that went into that unit. I wonder what it actually cost the government to make it back in the 1950s.
+Bob Wendoloski
I imagine it cost quite a bit. It's sure is built like a tank.
Is a piece of equipment like that still useful for today? Is it worth fixing and calibrating? I love his videos of old equipment and restoring them. He reminds me of my dad when he would fix his stuff.
It's funny, I have used a wobbulator, but it was a completely different thing. We used it to calibrate the sensors on rotating equipment that measured vibration. It had a rotating disk that was flat but eccentric. Imagine a record player with a spacer under one side. As the record turns you get an upwards movement and hen a downwards movement. We would measure this with a dial indicator, and we could calibrate our probes to this movement. Literately measuring how much it wobbled....
This is fantastic the thought into this is amazing
What advantage is the motor for the sweep generator? Why wouldn't they just do it with an electronic oscillator? Very good explanations. I'm addicted to thermionic emissions. Much of my Ham station is tube gear as well. You are much younger than me albeit much more educated. Why did you take an interest in tube gear? Thanks very much for the video's. I was never able to finish my EE. Your video's help fill in the gaps.
I think the problem is the technology to do the sweep back then was much more limited. Keep in mind that you need a linear relationship between the frequency and the sweep voltage, or else your frequency scale on the scope is going to look strange. You also need to sweep a very wide frequency range.
The only thing better than vintage tech is vintage military tech, great name for a device too, haha. Can't wait for your rebuild on this.
+Detecting History
Thanks!
Most oscilloscopes have a swept horizontal time base, so how would this differ from a regular oscilloscope? I have been around old test equipment for a while now, and this the first time I have seen or heard of such a unit. While I have seen external sweep generators before, I never had a need to use one.
The mechanical driven sweep circuit sounds similar to the electronic version of a Leslie speaker in which they used a motor to turn the plates of a continuous rotating variable capacitor and this is what caused the sound to shift from speaker to speaker, creating a stereo rotating speaker effect.
I think Louis Rossmann would shed a tear looking at this.
EICO test instruments made a wobulator sweep generator for radio MTV service. It was an effective and inexpensive way to do broad band alignment.
Something tells me this makes him happier than a $100 steak dinner.
That's awesome! Never seen inside anything like that. Looking forward to the rebuild. By the way...you have a beautiful lab.😄
+Jim Owen
Thanks for the kind comment Jim!
Great topic. I've heard of these but never looked into what they are/do. Thanx again for great vid.
+jp040759
Your welcome!
When I worked outside plant for the phone company as a young man, the saying then was that if the test meter wasn't heavy already, then they'd put it in a heavy box to make up for it.
That schematic looks like it was drawn by the same guy who drew up Leo Fender's schematics..... Very organized, logical, and fairly easy to follow. Those were the days......
Brick house. Would be very cool if you could get cases like that for building amplifiers.
Always wondered what in hell a wobbulator is. Now I know. Thanks for that!
Thanks. Liked the video and the explanation. Will be nice to see the wobbulator working once more.
+DAVET38
Thanks Dave!
Hi again Mr. Carlson. Would you mind sharing an high resolution image of the schematic for your wobbulator with a link for your subscribers as a reference for those who may also be restoring this type of equipment or just have a general interest in studying electronics? I had to look around quite a bit to find any documentation for the wobbulator online and I think it would be helpful if we subscribers could find it on your channel. Thanks for the great videos and keep up the good work!
+uomo d'onore
Hi, I snapped a few pix of the wobbulator schematic, but haven't even uploaded them yet. I will consider a file sharing account in the future.
That is a neat piece of test gear, oh the wobbulator that reminds me of my very first sweep generator, it was a very old Hickok and it used a regular speaker without the cone, it had a metal plate and was something like a vibrating capacitor, depending on how strong the AC voltage was applied to the "voice coil" determined the sweep width.
It just used a low 60 cps voltage on the "voice coil"
BTW, I never liked saying hertz, on these old things I like the good old CPS...LOL
+old64goat
Great story! I'm a CPS guy my self :^)
+old64goat I guess I'm an easy going person: Hz or CPS, SAE or Metric, C or F, it really doesn't matter to me.
A Radio Collector Mate gave me a 1970 Nordmende Wobbulator for free.
All the Tubes were pulled and for now it's only smoking, when I got space again to work on it I will try to restore it...
Thank's for the Explaination!
You're welcome!
Too bad the rebuild video didn't happen. It would have been interesting to get deeper into this thing.
Now that the labs are being moved, I will come across it again. It's behind about 10000 pounds of equipment in storage. It will have it's day on the bench :^)
Thanks Again for being so informative....
nice piece of kit, I am very much looking forward to the restore
+Mich smi
Thanks Mich!
Another wonderful teardown, thanx
+Jordan Rubin
Thanks Jordan!
still waiting for you to get back to this old beast....
Carl picks up a Collins R390A for a restoration process, alignment and replacement of components ... It would be very interesting to see his talent when dealing with a radio receiver such. A radio show receiver in the hands of a true artist of electronics.
+João Damasceno
Thanks Joao!
This looks like a Jack Davis or, more like Wallace Wood 1954 mad magazine cartoon. That observation aside, this is another of Mr Carlson's great example of the timeless quality equipment this country built..at one time.....
Wow, this is a fascinating device. Thank you very much for this video. I can't wait for the restoration videos.
+Mike M
Thanks Mike!
Looking forward to the restoration video. Thanks for sharing.
+Make Stuff Learn Stuff
Your welcome!
While serving in the U.S. Navy we had a saying that if it had handles on it, it was portable.
+Erik Thorsen
they were young top health people, so if you can lift it up, it's portable
+Erik Thorsen
LOL, I can see that!
A wobbulator sounds like something that needs it’s blinker fluid changed regularly
You mentioned the calibration dates, so Heres a tip on that. The reason for 6 months is the quality of the equipment didn't stay in calibration for much more than 6 months, so its reliability was in question. However if its cal. dates were say 3 years instead, then it could be a more reliable piece of test equipment. Signifying the calibration would tend to to be more dependable (Stay in Calibration for a longer period of time.)
11:42 Oscar Mike Gulf! Paul actually takes something apart on camera!
Really need to know how many things you have with a scope tube (green only ) no p4s or p7s allowed .?
I wobbulate. You wobbulate. He, she, we wobbulate. Wobbology the study of wobbulation!
I find it absolutely impossible to say wobbulator with a straight face.
I don't think you're alone.
Well, naturally, you need to bend your face a little bit in order to get the syllables out ;) .
@@MrCarlsonsLab Your tongue must be at just the correct angle.