MELF were just very popular back in the early surface mount days. Not sure exactly why. Maybe because it allowed manufacturers to leverage existing axial resistor factory lines to produce?
I'm working on a 2023A right now. The electrical design is as thoughtful as the packaging and construction. The RF amplifier stages each have active bias control so that there won't be variation in operating point unit to unit transistor differences or over temperature. The part of the generator I'm familiar with after working on it, is in my view elegant electronics design.
I think the first RF section you opened up is mostly the step attenuator (the center sections with the dividing "walls") - you pointed out the relays in each one, they switch in and out "pi"-type resistive attenuators. Regarding DDS, they are getting better (higher sample rates and bits of resolution) but I think most current signal generators use VCO-based synthesizers for lower spurious emissions.
Interesting video thanks! I've got the 2024 version here with the option 4 OCXO. The downside of the hi stability OCXO is you have to wait about 5 minutes after switch on for it to settle fairly well as the accuracy of the 10MHz OXCO is quite poor during the initial warmup time. Note also that the Analog Devices DSP chip at 13:30 is used for accurately synthesising the audio waveforms for the modulation modes rather than for sharing any control of the instrument.
We still use these at work, we have loads of 2024 2.4GHz versions with all the fancy options. The displays like to fail after a few years of operation and the mains filters make a lovely smell when they eventually go pop :)
I used to use it's older and smaller cousin as a radio transmitter, to repeat a station that was only receivable in one spot to the rest of us. Did some spoofing at times of other stations.......
I truly believe that 99% if not more of the population of earth wouldn't have a clue what your talking about!!! It is utterly amazing how much effort must have gone into the production of this product! and equally amazing is your understanding of how it works in modular sections!
I love tear down Tuesday, can you make a playlist with all your tear downs on ? That would be brutal and I would love it. And im sure the other peeps would too ❤️😎
RF PORN! I Love It. I saw a number of inductors and transformers as well as crystals. In your teardowns, could you discuss these as well and describe their contribution to the circuit?
Feed-trough caps called perpetrators lol :) That was on the step attenuator.. Talk about make stuff up as you go.. Thumbs up for effort & entertainment!
Free upgrade of the scope to 1GHz? ... jammy b**!! But you deserve it! Agilent got a sale of a DSOX-3000s series scope from myself on the back of your review/teardown. The teardown in particular sealed the deal.
I wonder how often that was done? I remember someone used to rebroadcast Capital Radio around the University of Bath campus to bring a bit of London to those of us wanting a reminder of home...
досмотрел до конца . очень серьёзный зверюга . внутри сделано по уму . ну а харакеристики его они и так наружи в прямом и переносном смысле . понял из увиденого как внутри , нужно бережно относиться к машинке и не допускать возможности случайно спалить выход апарата исследуемым трансивером в нештатном ( передающем ) режиме . исключить возможность передачи во время испытаний и только на приём .
Great vid good to see inside i love marconi equipment too i have a 2022D generator nice bit of kik thing it is older than the one you examined, Also i have a 2955 radio test set be great if you got the chance to do a tear down on one of those , but yeah reelgood quality miltary spec equipment , Marconi made the clansman military radios and most of there equipment was to that high standard too i ues to work on the radios and used many marconi pices ok keep up the good work
The only thing they could have done better is to mark where the beryllium is on the die cast shield. Maybe they did that in the manual you were supposed to read?
Urgh, trying to fix one of these and found that one of the pads is damaged, either the bad itself or one/both of the relays. Really not looking forward to taking it apart, considering the EMI gasket is all dried up and dead, so that's about £30 of replacements from the start. Relays are way more expensive (£100 each, 2 per att), so hopefully it's the pad with it's cheap pi attenuator resistors. Bastard thing had me chasing all around the RF section as I was trying to fix an AM mod unlevel (508 error) issue, and then suddenly it lost like 30db of power, so I thought I'd blown one of the preamps, or the leveling section. Still, I love the style of design from this area, seems to be really logically laid out unlike some of the older kit that didn't have SMD tech.
I love your teardowns Dave. The whistling sounds like a songbird at 7:25. Looking up mu-metal had me trapped in Wikipedia for two hours. Start with mu-metal, and finally stopped with explosive bolts?
I got a question... How long did it take to put it back together? :) Actually you kept it in tact quite a bit... yet you still had a huge pile of screws/bolts. That was crazy.
I used to work for Aeroflex in the RF switch division. We had a few Aeroflex spectrum analyzers (Completely different division), and ya, they were pretty shitty. HP/Agilent all the way.
Here's where we last left Flash on the IFR saga. Yes, IFR was purchased by Aeroflex out of New York. This allowed IFR to have better control over the prices of RF attenuators and like items, which are pretty expensive even at the wholesale level. Anyways, in 2014, Cobham Plc. bought Aeroflex, probably for the ability to make inroads as a military vendor in the U.S. fairly early on, they cut loose with Aeroflex N.Y. And late last year, Cobham cut loose of the Wichita KS manufacturer. Instead of reverting to their former IFR identity, they were picked up by another concern, and now their "nom du jour" is Viavi. As for Marconi Instruments, that was a brand that was purchased not too long after Aeroflex acquired IFR. Though the latter certainly had the capacity to bring the Marconi manufacturing to their Wichita facility, Marconi remained a purely British undertaking. After a while though, many of the Marconi gear was rebranded with the Aeroflex name. And there was a lot of Marconi generators like the 2023 in use at the Wichita plant. Even though it bore a different name, Marconi made those units in England, and they were quite insistent that they be serviced there too. While it would have been nice to be able to have a service depot in the middle of America, alas Aeroflex became a middleman for Marconi support. Glad that I could share the story of dueling brands, where whole companies are shifted from bean counter to bean counter. Caio!
What would you use a sine wave or something at 600Mhz for exactly? After paying the 1000s for it? Doesn't like wireless usb sticks generate as complex encoded rf signal and it costs like $10?
cпасибо за показательный коментарий со вскрытием апарата . приобрёл себе Marconi-2024 ( 9 KHz - 2,4 Ghz ) отличнейший аппарат !!!! не надо свой вскрывать когда праздное любопытство удовлетворено ( а что внутри ? ) спасибо автору ролика за удовлетворение детского вопроса от взрослого дяди .
Had a few friends that worked for GEC back in the day almost followed them, they worked on military radars... I still don’t know why expensive gear like that doesn’t come with a decent OCXO as standard...
A lot of the facilities that would use gear like this will have a master cesium or rubidium 10 MHz source, and lock all the gear in the facility to it. There was an external reference BNC on the back panel.
Bob Weiss probably true, I’ve worked in dozens of labs throughout the years and not many had a building wide reference clock source and most production environments I’ve been in don’t either. The only time I’ve seen an atomic clock reference source was when I was at Siemens and also AT&T they where usually in an actual metrology lab where equipment like this would be the little guy. I think for a instrument that’s in the $10,000 price range (or whatever the original cost was) another $300 for a decent XO should just be standard IMHO... So in my experience something like this would normally only be connected to a Rubidium source while it was being calibrated, but I might just be unfortunate lol...
Love this video. Nowadays the ADF4350/1 can do the same job and even go to 4.4GHz! Love the many compartments. I recognised the varactor diodes in the VCO (black parts with yellow stripes x 6 at 27:56on the left). Memories from the 90s
It's not uncommon for RF power devices to be encased in beryllia ceramics. And btw beryllia won't really harm you unless something is done to compromise the integrity of the ceramic.
The comment that Dave made about Marconi going for ultra reliable power supply is kind of ironic. We had a bunch of these in our lab (about 10). Almost half of them died due to failed power supplies. It was a pretty easy fix but pretty remarkable at the rate they are dying.
WHA? :) Obviously he's whistlin', just curious WHAT he's whistlin'. I would guess it ain't dixie. And I wouldn't be so sure about the speed-screwing (or un-screwing). He's an Aussie after all, and they're a clever bunch. Check out @Aussie50 too :)
Too bad it doesn't go to 1.21 Gigahertz... But that doesn't go with the Indiana Jones you were humming anyways. Love the RF porn, and the system engineering that went into this thing.
It's a shame they used those SMT electrolytic capacitors instead of tantalum. I've seen tons of them bad in camcorders and they are hard to change. I'm surprised to see that it will change in 1 Hz increments, I expected maybe 10KHz steps. Now I know why these are so expensive. Wish I had one, would make designing RF equipment much easier.
If you don't need the low ESR of a tantalum, the aluminum electrolytic will have higher reliability. The high rate of failures of aluminum electrolytics that plagued the industry ten or fifteen years ago related to problems with the electrolyte. The formula was stolen and copied incorrectly. Do a google search on electrolytic capacitor stolen recipe.
TiredOldFart I remember reading about that, and lately I'm finding that the tantalums aren't that good after all. The Tektronix oscilloscopes, mainly the 485 seems to always get shorted tantalum capacitors, I'm considering changing them all to aluminum electrolytics. I have two of them, sometimes the shorted cap temporary goes away but always keeps coming back, makes it a real pain in the ass to find the bad cap.
One hertz steps. Now that's HF porn. Love it! I'd have one in a second (if I could afford it?) but I'm still working on an excuse for buying a Fluke 87V when I have a pristine AVO Megger...
I posted a video response but i cant find it, Anyway Dave if you see this, i have made an intro for your video's its on my channel if you can find it, Let me know what you think
MELF were just very popular back in the early surface mount days. Not sure exactly why. Maybe because it allowed manufacturers to leverage existing axial resistor factory lines to produce?
I'm working on a 2023A right now. The electrical design is as thoughtful as the packaging and construction. The RF amplifier stages each have active bias control so that there won't be variation in operating point unit to unit transistor differences or over temperature. The part of the generator I'm familiar with after working on it, is in my view elegant electronics design.
I loved the seeing the block diagram as you were going along. Keep up the good work!
I think the first RF section you opened up is mostly the step attenuator (the center sections with the dividing "walls") - you pointed out the relays in each one, they switch in and out "pi"-type resistive attenuators. Regarding DDS, they are getting better (higher sample rates and bits of resolution) but I think most current signal generators use VCO-based synthesizers for lower spurious emissions.
16:30, that's just a semi rigid coaxial. A nice and thick one though.
It is LCD, I was just saying it had that bright VFD type look to it.
Interesting video thanks! I've got the 2024 version here with the option 4 OCXO. The downside of the hi stability OCXO is you have to wait about 5 minutes after switch on for it to settle fairly well as the accuracy of the 10MHz OXCO is quite poor during the initial warmup time. Note also that the Analog Devices DSP chip at 13:30 is used for accurately synthesising the audio waveforms for the modulation modes rather than for sharing any control of the instrument.
We still use these at work, we have loads of 2024 2.4GHz versions with all the fancy options. The displays like to fail after a few years of operation and the mains filters make a lovely smell when they eventually go pop :)
Yeah, I love MELF, very 80's/90's
The way the RF board is canned in the machined area makes it feel like it came from space, it oozes ultra-high quality!
I used to use it's older and smaller cousin as a radio transmitter, to repeat a station that was only receivable in one spot to the rest of us. Did some spoofing at times of other stations.......
Yep, most high end gear like this is designed to be 19" rack mounted.
I truly believe that 99% if not more of the population of earth wouldn't have a clue what your talking about!!! It is utterly amazing how much effort must have gone into the production of this product! and equally amazing is your understanding of how it works in modular sections!
I love tear down Tuesday, can you make a playlist with all your tear downs on ? That would be brutal and I would love it. And im sure the other peeps would too ❤️😎
RF PORN! I Love It. I saw a number of inductors and transformers as well as crystals. In your teardowns, could you discuss these as well and describe their contribution to the circuit?
Feed-trough caps called perpetrators lol :) That was on the step attenuator.. Talk about make stuff up as you go.. Thumbs up for effort & entertainment!
Free upgrade of the scope to 1GHz? ... jammy b**!! But you deserve it! Agilent got a sale of a DSOX-3000s series scope from myself on the back of your review/teardown. The teardown in particular sealed the deal.
I wonder how often that was done? I remember someone used to rebroadcast Capital Radio around the University of Bath campus to bring a bit of London to those of us wanting a reminder of home...
Beauty!
досмотрел до конца . очень серьёзный зверюга . внутри сделано по уму .
ну а харакеристики его они и так наружи в прямом и переносном смысле .
понял из увиденого как внутри , нужно бережно относиться к машинке
и не допускать возможности случайно спалить выход апарата исследуемым трансивером
в нештатном ( передающем ) режиме . исключить возможность передачи во время испытаний и только на приём .
@ 22:06 Silk screen printing is wrong. It shows 2 relays designated RLE. The second one should be RLJ.
I wonder if the current model is UK made? I doubt it...
Who else was on the edge of their seats at the 24 minute mark? :D
Fantastic stuff!
Great vid good to see inside i love marconi equipment too i have a 2022D generator nice bit of kik thing it is older than the one you examined, Also i have a 2955 radio test set be great if you got the chance to do a tear down on one of those , but yeah reelgood quality miltary spec equipment , Marconi made the clansman military radios and most of there equipment was to that high standard too i ues to work on the radios and used many marconi pices ok keep up the good work
Piece of Art!
Also, TV cameras, analog video processors...
Its interesting to note that most of the passives are MELF packages, you don't see them much anymore.
No idea. Just likely a small mod they decided they needed after it hit production.
awesomesauce! thaks david
The only thing they could have done better is to mark where the beryllium is on the die cast shield. Maybe they did that in the manual you were supposed to read?
Urgh, trying to fix one of these and found that one of the pads is damaged, either the bad itself or one/both of the relays.
Really not looking forward to taking it apart, considering the EMI gasket is all dried up and dead, so that's about £30 of replacements from the start. Relays are way more expensive (£100 each, 2 per att), so hopefully it's the pad with it's cheap pi attenuator resistors.
Bastard thing had me chasing all around the RF section as I was trying to fix an AM mod unlevel (508 error) issue, and then suddenly it lost like 30db of power, so I thought I'd blown one of the preamps, or the leveling section.
Still, I love the style of design from this area, seems to be really logically laid out unlike some of the older kit that didn't have SMD tech.
I love your teardowns Dave. The whistling sounds like a songbird at 7:25. Looking up mu-metal had me trapped in Wikipedia for two hours. Start with mu-metal, and finally stopped with explosive bolts?
that power supply case might've been large enough to also accommodate the DC power supply if it was to be fitted.
i want such a device but i have no idea what to use it for :P
What you call 'penetrators' are actually feed-through capacitors...
Either that or they had the choise of another layer on the board or one green wire.
EPROMs do exist in CLCC, CPGA and CDFP (ceramid dual flat pack) packages but you almost never see them outside of military hardware...
I've got a few ceramic DIP UV-erasable EPROMs in my junk box. I think they came from an old ECU.
How does one install option 12, Sinad measurment ?
You should have plugged it in to the oscilloscope with all of the shielding removed to see what the output looks like.
My 30 year old Gould 20 MHz analog scope is made in England, and my HP 54501A is made in USA :).
Aren't those white standoffs (in the powersupply) made from ceramic material (because of the heat)?
Is there any reason for going with MELF components over other surface mount packages? Would it be the power handling capability?
I got a question... How long did it take to put it back together? :) Actually you kept it in tact quite a bit... yet you still had a huge pile of screws/bolts. That was crazy.
That's a neat little power driver you're using there. What make is it?
Isn't it great when there is an RS-232 port on things.. USB blows, RS-232 is the ultimate serial shell
Shield inside the shield ... We need to go deeper .
Buy one anyway, they are cool!
lmfao @ dave's whistling sped up 7:25
great stuff
I used to work for Aeroflex in the RF switch division. We had a few Aeroflex spectrum analyzers (Completely different division), and ya, they were pretty shitty. HP/Agilent all the way.
I wonder if Aeroflex still makes them in England. What used to be IFR Systems is based not too far from where I live in Wichita, KS.
Here's where we last left Flash on the IFR saga.
Yes, IFR was purchased by Aeroflex out of New York. This allowed IFR to have better control over the prices of RF attenuators and like items, which are pretty expensive even at the wholesale level. Anyways, in 2014, Cobham Plc. bought Aeroflex, probably for the ability to make inroads as a military vendor in the U.S. fairly early on, they cut loose with Aeroflex N.Y. And late last year, Cobham cut loose of the Wichita KS manufacturer. Instead of reverting to their former IFR identity, they were picked up by another concern, and now their "nom du jour" is Viavi.
As for Marconi Instruments, that was a brand that was purchased not too long after Aeroflex acquired IFR. Though the latter certainly had the capacity to bring the Marconi manufacturing to their Wichita facility, Marconi remained a purely British undertaking. After a while though, many of the Marconi gear was rebranded with the Aeroflex name. And there was a lot of Marconi generators like the 2023 in use at the Wichita plant. Even though it bore a different name, Marconi made those units in England, and they were quite insistent that they be serviced there too. While it would have been nice to be able to have a service depot in the middle of America, alas Aeroflex became a middleman for Marconi support.
Glad that I could share the story of dueling brands, where whole companies are shifted from bean counter to bean counter. Caio!
What would you use a sine wave or something at 600Mhz for exactly? After paying the 1000s for it? Doesn't like wireless usb sticks generate as complex encoded rf signal and it costs like $10?
Because of accuracy. Generating such frequencies is not difficult, but being able to precisely control them in 1 Hz increments is.
Ah yes, good point.
The datasheet inside reminds me of surgeons who leave their tools inside the patient...
Probably rack mount.
You can get rails for most of these
cпасибо за показательный коментарий со вскрытием апарата .
приобрёл себе Marconi-2024 ( 9 KHz - 2,4 Ghz ) отличнейший аппарат !!!!
не надо свой вскрывать когда праздное любопытство удовлетворено
( а что внутри ? ) спасибо автору ролика за удовлетворение детского вопроса
от взрослого дяди .
Had a few friends that worked for GEC back in the day almost followed them, they worked on military radars... I still don’t know why expensive gear like that doesn’t come with a decent OCXO as standard...
A lot of the facilities that would use gear like this will have a master cesium or rubidium 10 MHz source, and lock all the gear in the facility to it. There was an external reference BNC on the back panel.
Bob Weiss probably true, I’ve worked in dozens of labs throughout the years and not many had a building wide reference clock source and most production environments I’ve been in don’t either. The only time I’ve seen an atomic clock reference source was when I was at Siemens and also AT&T they where usually in an actual metrology lab where equipment like this would be the little guy. I think for a instrument that’s in the $10,000 price range (or whatever the original cost was) another $300 for a decent XO should just be standard IMHO... So in my experience something like this would normally only be connected to a Rubidium source while it was being calibrated, but I might just be unfortunate lol...
@EEVblog What's that whistling between 7:20 and 7:30? :D
Brilliant British manufacturing!
"..and they marked it on the silkscreen.....BerylliumT !!...."
Wish I had those.
These are US$5700 each new. Really not too bad when you consider that you are getting equipment designed for avionics work.
Finally some interesting hardware :)
Like the Raspberri PI :O
That's for people to figure out!
RF RULES!
Love this video. Nowadays the ADF4350/1 can do the same job and even go to 4.4GHz! Love the many compartments.
I recognised the varactor diodes in the VCO (black parts with yellow stripes x 6 at 27:56on the left). Memories from the 90s
25:00 Shieldception!
Background noises @ 7:20 :D
It's not uncommon for RF power devices to be encased in beryllia ceramics. And btw beryllia won't really harm you unless something is done to compromise the integrity of the ceramic.
The comment that Dave made about Marconi going for ultra reliable power supply is kind of ironic. We had a bunch of these in our lab (about 10). Almost half of them died due to failed power supplies. It was a pretty easy fix but pretty remarkable at the rate they are dying.
What failed?
That's Marconi.
Where can I find that block diagram?
He's obviously just whistling while he works. Notice he cannot actually screw that fast in real time ;)
WHA? :) Obviously he's whistlin', just curious WHAT he's whistlin'. I would guess it ain't dixie. And I wouldn't be so sure about the speed-screwing (or un-screwing). He's an Aussie after all, and they're a clever bunch. Check out @Aussie50 too :)
It surely takes some balls to tear apart such an expensive piece of pornographic hardware. How do you manage not screwing it up/breaking it?
02:57 ERROR 102 RF LEVEL LIMIT
The screen looks like a graphic LCD with a bright backlight. It doesn't look like a VFD to me.
Too bad it doesn't go to 1.21 Gigahertz... But that doesn't go with the Indiana Jones you were humming anyways.
Love the RF porn, and the system engineering that went into this thing.
Aaah you worked for Marconi!! So sad the way the company went. A case study in poor management. RIP.
It's a shame they used those SMT electrolytic capacitors instead of tantalum. I've seen tons of them bad in camcorders and they are hard to change. I'm surprised to see that it will change in 1 Hz increments, I expected maybe 10KHz steps. Now I know why these are so expensive. Wish I had one, would make designing RF equipment much easier.
If you don't need the low ESR of a tantalum, the aluminum electrolytic will have higher reliability. The high rate of failures of aluminum electrolytics that plagued the industry ten or fifteen years ago related to problems with the electrolyte. The formula was stolen and copied incorrectly. Do a google search on electrolytic capacitor stolen recipe.
TiredOldFart I remember reading about that, and lately I'm finding that the tantalums aren't that good after all. The Tektronix oscilloscopes, mainly the 485 seems to always get shorted tantalum capacitors, I'm considering changing them all to aluminum electrolytics. I have two of them, sometimes the shorted cap temporary goes away but always keeps coming back, makes it a real pain in the ass to find the bad cap.
TiredOldFart thanks for the heads up😆
$100 relay? This thing better wipe my bum.
One hertz steps. Now that's HF porn. Love it! I'd have one in a second (if I could afford it?) but I'm still working on an excuse for buying a Fluke 87V when I have a pristine AVO Megger...
Penetrator = australian for 'feedthrough capacitor '......
sorry man i didn't notice that.
Hahaha! Datasheet (==p0rn for engineers) inside. Very nice :D:D
Because ... MOST END UP LYING ON FLOOR !
modulated*
Tell us the price son:)
holy sh!t
I posted a video response but i cant find it, Anyway Dave if you see this, i have made an intro for your video's its on my channel if you can find it, Let me know what you think
i'd have to harvest alot of organs for selling on the black market to afford one of these
I thought that paper was going to be porn. The aforementioned statement made it seem like it could have been.
I see this model going for $1,700+ on ebay. spendy gear.
"shake proof nuts" ;)
The brand appears to be owned by an American company called Aeroflex now. Shame.
Made in England :)
2000.000 Mhz WTF
Got my one today :) its the IFR 2025 and yeah a lot of porn inside. Amazing (Actually got 2 of those)
don't think so haha
Seems to be just ramdomness...