I recall my parents had this exact model. Yellow screen and all. The TV repair man came by so often he became a member of the family when he proposed to my aunt. The set was replaced in 1957 with an 21" Emerson.
We had a Hoffman TV when I was a kid. We were the first ones our neighborhood in San Diego that had a TV and I remember the neighbors would visit just to watch the TV. I think I was about 4 or 5 and I was convinced that the Lone Ranger lived inside the TV. We had that TV until the early 60's, it was a monstrous table top model that sat on a swivel table, the cabinet and table were solid mahogany. It was called and "Easy Vision Television." The tuner dial didn't click into the station but dialed like a radio.
The last one I worked on was back around 1978.I had two and both had the same problem:the .0039 pf tube under the 12BY7 vertical output tube,would open and the tube would run wide open and go into foldover.The first one I owned did that.It was a beautiful set that had electronic tuning-one button for up,one for down.It was given to me in 1976 by my second grade school teacher.I found the trouble by way of some freeze spray and referring back to the capacitor theory I learned from an old,old copy of "Everybody's Radio Manual" from 1954.The second Hoffman I owned was a cheesier looking model I gave to my brother.
I must say Mr Shango you do a very good job if you are the type of person and inclined into this sort of thing you really do lay out a very good format on how to diagnose where to get schematics tools you'll need I have become quite adapted to fixing old school analog televisions solely on your videos although I am someone of the newer tech generation but learning this old stuff really honed everything in quite nicely good show brilliant
Interesting mix of circuit design on this set. Autotransformer-type flyback and vertical output transformers with cathode coupled multivibrator horizontal oscillator stage--all features that would become standard on more modern sets. The 21.6 Mhz sound I-F frequency is interesting as well as being very nonstandard, even for the time of manufacture (I wouldn't want the job of aligning this I-F system). Such a high frequency clearly indicates a split-sound design for that stage. As you probably know, fine tuning was very critical in such a design, and in fact a user would fine tune this sort of set for best sound as opposed to going for the best picture as is done when fine tuning a set with the industry standard intercarrier sound I-F system. The condition of the tuner probably explains why you had a hard time getting TV audio out of the thing. Too bad about the CRT. Fully restored this set would be one heck of a conversation piece in anyone's den.
What a stupid design as you say, also imagine the extra power usage when only listening to the radio. Great to hear Chris on the background too. That tune amp is a pure beauty.
Suchalongname Bythetimeyouaredonereadingthisitsover Not really, it's just weird to imagine how people 60 or 70 years ago would of reacted to modern rap or something like that, if they could've somehow head it. Makes me think about time travel, lol, :-)
I picked up a 1951 Philco console Phono / radio last summer and I got it home and powered it up and I went through the Am band (nothing but talk and two OLDIES stations)Nothing weird. I switch to FM and (I'm in western Oklahoma) I hit 4 or 5 country stations, it's all good, then I hit the local hip hop station playing something like Black Eyed Peas or whatever I literally yanked my hand away like I had been electrocuted, lol. It seemed SO WEIRD! So yeah I know exactly what you mean!!
I received the same feeling, watching a trashy piece of television content, on a 1962 Panasonic that Shango66 refurbished. Shango66 rightfully made fun of the woman featured on this tube. "Escalaye!"
Hi Shango066, I am enjoying your TV repair Videos a lot here, It brings back good old memory's of My Days at Grand TV way back in 1978 how ever I find it incredible to see you get these very old TVs from 1951 & stuff. We never got any thing this old at the TV shop I use to work at in Duluth MN back in 1978 But We did get a lot of 1967 RCA floor model TV sets in that needed the big silver caps replaced & We worked on lots of Zenith TVs as well & other brands. Most of the TV We would get at Grand TV were lots from the late 1960s & lots of color & B&W TV from 1970 & up to the mid 1970s & new late 1970s TV that had some defects That Grand TV fixed. We did have one old round color CTR TV come in that was an RCA TV & the Flyback was shot it started smoking When my friend Mike went to check the high voltage on it. the Flyback was no longer available & the owner did not want to have it fixed. Grand TV sold new 19" TV sets, The RCA XL 100 was one brand & Zenith all so as well. I sure wish I could meet you, But I live way up in north eastern MN But I wish I could hook up with you some how. I had a VCR Business on my own from 1987 till 2002 & at that point VCRs became to cheap to fix. It's so cool how you find these very old sets & get them all working. Now today even with the HD flat screen sets We have all kinds of very odd Makes & Zenith & other good name brands are not making TVs any more like it was in the olden days. Take care, Jerry C.
Your videos are great...you, uncle Doug and radionut have caused me to try my hand at repairing old tube radios...of course I started on a Philco 37-641 and am banging my head against the wall with low volume issues. I'll figure it out sooner or later...probably see you do something that will point me in the right direction.
+shango066 Hi, it's a new subscriber here. I've been watching your videos for years, but I ususally use TH-cam without logging in. Today, I've logged in after a long time, so I decided to subscribe right now. I also collecting vintage TVs and radios here in Hungary, and found very interesting to see these US made sets. I like yours and Bob Andersen's channel as well in this topic. Two completely different approaches of restoration, Bob virtually rebuild his sets replacing all capacitors and most of the carbon-paste resistors, uses modern resistors and film capacitors, while you are just replacing the components essential to get a working set, and don't bother with checking all component values being inside their tolerance ranges. I also like to see the possible highest count of original components in my sets, so I also replacing just which are necessary to, and if I have to replace something, I am striving to use NOS components if possible. But I like Bob's approach also, and he frequently working on such old and/or bad condition sets that really deserves that level of care. TV broadcasting started in 1957 here in Hungary, so we don't have pre-war sets, my oldest ones are from the early '60s, and they have a very high ratio of factory original components. Our first color sets were made in the mid '70s, only 2 type were made with tubes and delta-CRT, all the later ones were solid state and used in-line CRTs. They are very rare nowadays, unfortunately I haven't got any of them, I have just some B/W tube sets, and vintage solid state color sets from the '80s.
+mrnmrn1 Bobs approach is no doubt the right way to restore a vintage set. I like to get them working and verify no major defects before I go all they way. As you can see the burn spot on the CRT on this set makes it less describable and lower priority than many of the other sets I have that need to be restored. I am with you on keeping the maximum amount of original parts but capacitors are a major issue most of them time on sets this old. There will be follow up on this set but not right away.
first time I ever saw a capacitor smoking! That TV sorta reminds me of my grandparents Dumont. Same 19" round metal CRT, and Mallory indotuner? Actually the TV sound subcarrier IF is about the same bandwidth or LESS than standard FM, so yeah, the indo tuner would work on FM. In fact my grandparents Dumont tuned FM between channels 6 and 7 along with the aircraft band (somehow got AM) and the 2 meter ham band. It even had a dual speed vernier drive and a slide rule dial that expanded the section between 6 and 7 to tune the FM band (complex gearing and dial string drive IIRC). 6AL7 eye tube poked in the middle of the dial. Ion burn doesn't mean that the CRT had the wrong gun! There was a system that had a straight fire gun with TWO iron trap magnets, but if you didn't get those magnets set up just right you'd burn the screen. There was a diagonal cut inside one of the gun elements that directed the beam off to the side INSIDE of the gun, you can't see that well from outside of the tube. I quote: "a 'slashed-field' gun was used and the G2 and first anode elements were cut diagonally to form a slant electron lens which caused the electrons and ions to be bent towards the neck and the double ion trap was used to first move the electrons slightly up and the second magnet to bring the electrons up to be aligned with the electron gun aperture disc. Apparently if a large magnet was used it would bend some of the ions up as well. Later the electron gun itself was bent towards the neck wall and this only required a single magnet trap to move the electrons up. This info is more clearly explained in The Cathode-Ray Tube by Peter Keller."
Robin Sattahip , same observation here. Bad capacitors in any tube set can, and do, destroy other associated components, some of which are almost impossible to obtain today. Best advice is to replace all of these paper capacitors and avoid destroying the other parts.
Remember a Hoffman console TV in the basement of our Denver Colorado house when I was little.The Hoffman was OUR set and the brandnew metal "bucket" model Zenither was for Mom and Dad-Sometimes when a really good show came on-we all watched on the Zenith.The Hoffman we had had a green screen-kinda like an older computer monitor.I watched Mickey Mouse,Superman,Howdy Doody,and others on that Hoffman.Ours would have been like the one shown but didn't have the tuner or the TT.
Dumont made CRTs with straight guns for several years, they all had ion burns, the burn would be there even if rebuilt. My Stromberg Carlson (Dumont clone) has the burn, later 16" metal bell tubes had aluminized screens but they are kind of rare.
This is a "split sound" TV. Instead of treating the sound carrier as a 4.5 MHz subcarrier that is picked off after the video detector, it has its own IF strip at 21.6 MHz. One disadvantage of this approach is that when watching TV, the fine-tuning would be absolutely critical. Mistune by a slight amount, and the sound will go bye-bye.
I put the Parallel "T" Bass Shaping Filter seen at 8:26 into a circuit simulator. That thing is a combination of a high pass filter and a 10 Hz notch filter. So no loudness or bass boost or anything like that. I wonder what that is good for.
Video looks great even at full screen. Sounds is good too. I'd try to get that unit completely restored, record player and all. A fine example of early 50's "all-in-ones"! Oh by the way, you can't call the caps "bumblebees", then you'll offend real bumblebees. You'll probably just have to call them those "thingies".
I could be stupid,but I just found me a Hoffman in pretty fair shape.. brought it up slowly with a variac just to see if the pic tube had any life, it did,and immeadiatly removed all power. being that it is a 1950 model pushing 70 years old, why would you not just replace all caps, all resistors, the start trouble shooting, this would include giving all pots and tuner a complete bath and checking all tubes to include mutual conductance values.
If you are going to replace all components with modern Chinese ones, then why not throw the whole thing in the garbage and get a Chinese TV from Wal-Mart? The resistors are almost never bad, the capacitors are rarely bad enough to be the fault, and electrolytics of this era are rarely totally bad. Do you have no interest in getting the set running on as original components as possible?
@@gregorymalchuk272 The sand resistors always go bad and bumblebees short almost always. They already had a failed sand resistor and a bunch of bumblebees.
@@jussapitka6041 I've never had a sand resistor go bad on me, though most of the old paper capacitors are junk. That said, most of my stuff is running on original equipment, with minor repairs.
I remember as a boy our b+w TV was fixed by a neighbor. Could you reccoment a free good book to learn about tube TVs? I have restored many valve radios. I learn a lot watching your clips. Thank you.
+shango66 i like the way you make old CTR and vintage tv i have two old tvs that broken have a broke lamp i wanted to ask you to fix it but i live in NL
Good job you guy's (shout out to Chris71) It's still worth saving even though the CRT had Ion burn in the middle. Few of those old machines worked well (by today's standards). Yes, Those "Bumble-Bee's are junk, but you might be surprised how much naive guitarists are willing to pay for them on E-Pay. They were used in many old guitar amps of old. Many of the Bumblr's have a shorter life than those vertical canned electrolytics. IMHO, you should save the Hoffman from the dumpster. 'Shirley' it will be a great prop for the future movie business. 73'
I'm curious about the TV tuner - is it inductively tuned? Also noticed the sound tuning is real sharp. Evidently this set doesn't use intercarrier sound. On those set you have to set the fine tuning to get sound and take what you get for the picture.
Ahh, the Hoffman.....I was hoping you'd get back to it. Just my two cents, but I'd fix it. I know the ion burn is a bummer, but it will still work for now....and later you might be able to find another crt for it. The caps in that think are junk, you might be better off just shotgunning them all at once.
Weak damaged CRT is a bummer. But my vote is fix it up. Never know when a tube might fall in your lap and besides what a nifty F&&king set. Craftsmanship inside and out. Is there the possibility of retrofitting a different more common CRT into this one? Anyway nice vid man!
+shango066 Are you never try to rejuvenate a tube? AFAIK, if a CRT (or any tube) is stressed only by heating, without applying bias, causes different type of degradation than normal use. Mainly cathode poisoning, which affects mostly the surface of the emitting material, therefore it may can be removed either with a delicate, low current rejuvenation. If I were you, first I would try to ground the cathode, to give the CRT an 'infinite' beam current, sometimes it's enough to burn away the poisoned layer of the emitting material, and burn the possible cathode-g1 bridges caused by the evaporation of the cathode material. I don't understand why CRT rebuilders were used straight guns for originally tilted-gun CRTs. If tilted-gun assemblies were no longer available, why don't they aluminised the re-built CRTs before re-assembly? They had all the stuff for re-building a CRT, I don't think that the aluminising would be a big problem for them. I think they only need a rubber plug to the cutted-neck CRT, with a tungsten filament going through it, mount the right amount of high purity aluminium among the turns of the tungsten filament, then suck the CRT to high-vacuum with that rubber plug applied, warm the tungsten filament until white-glow to evaporate the aluminium, and that's it. Am I wrong?
I would have saved myself a lot of misery, and maybe saved that 150 ohm by replacing every cap in that entire set before I ever turned it on. It is not worth the chance with those old units.
I know that the last guys in the US that rebuilt CRTs went out of business a few years ago,but have you talked to people like arcademonitor.com or Pinball Medic who rebuild CRTs for old arcade video games? How is the CRT Rebuilding Project from the Early Television Museum coming?
If I were you I would have a whole new modern TV with color. put in the cabinet . I would not go throught all the trouble tring to make that old TV work.
00:18:00 Bien con esa válvula, en remover los contactos del zócalo. ✌👍📺📻 00:20:00 Good afternoon, please, you can't add subtitles in Latin Spanish. Thanks and regards from Buenos Aires, Argentina. And that smoke? Is it from the Flyback? What happened to the tension? 00:21:57 Excelente Sonido 🔈🔉🔊🔊🔊🔊 00:25:18 Buena alimentación de señal. To have capacitor de acoplamiento en buen estado? 00:28:28 Good TV 📺 is a channel Spanish ✌✌✌ IS FM OR TV?
+David Okanagan No, it's not, it was a fairly high end set for 1951 as it has built in AM/FM radio included, along with a record changer. I don't think Hoffman ever did make anything that's considered low end.
![[#2024MAMA] BIGBANG (빅뱅) - 뱅뱅뱅 (BANG BANG BANG) + FANTASTIC BABY | Mnet 241123 방송](http://i.ytimg.com/vi/EQsYfiPR9uM/mqdefault.jpg)
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I recall my parents had this exact model. Yellow screen and all. The TV repair man came by so often he became a member of the family when he proposed to my aunt. The set was replaced in 1957 with an 21" Emerson.
Lol imagine tv being so POS that you have to marry a repairman
Maybe your aunt kept sabotaging the tv so that tv repairman she fancied would come over to fix it
That Simpson's scene were patty unplugs the tv so the TV repair man is lured into the apartment
this is the most interesting story I heard today
We had a Hoffman TV when I was a kid. We were the first ones our neighborhood in San Diego that had a TV and I remember the neighbors would visit just to watch the TV. I think I was about 4 or 5 and I was convinced that the Lone Ranger lived inside the TV. We had that TV until the early 60's, it was a monstrous table top model that sat on a swivel table, the cabinet and table were solid mahogany. It was called and "Easy Vision Television." The tuner dial didn't click into the station but dialed like a radio.
The last one I worked on was back around 1978.I had two and both had the same problem:the .0039 pf tube under the 12BY7 vertical output tube,would open and the tube would run wide open and go into foldover.The first one I owned did that.It was a beautiful set that had electronic tuning-one button for up,one for down.It was given to me in 1976 by my second grade school teacher.I found the trouble by way of some freeze spray and referring back to the capacitor theory I learned from an old,old copy of "Everybody's Radio Manual" from 1954.The second Hoffman I owned was a cheesier looking model I gave to my brother.
I must say Mr Shango you do a very good job if you are the type of person and inclined into this sort of thing you really do lay out a very good format on how to diagnose where to get schematics tools you'll need I have become quite adapted to fixing old school analog televisions solely on your videos although I am someone of the newer tech generation but learning this old stuff really honed everything in quite nicely good show brilliant
Interesting mix of circuit design on this set. Autotransformer-type flyback and vertical output transformers with cathode coupled multivibrator horizontal oscillator stage--all features that would become standard on more modern sets. The 21.6 Mhz sound I-F frequency is interesting as well as being very nonstandard, even for the time of manufacture (I wouldn't want the job of aligning this I-F system). Such a high frequency clearly indicates a split-sound design for that stage. As you probably know, fine tuning was very critical in such a design, and in fact a user would fine tune this sort of set for best sound as opposed to going for the best picture as is done when fine tuning a set with the industry standard intercarrier sound I-F system. The condition of the tuner probably explains why you had a hard time getting TV audio out of the thing. Too bad about the CRT. Fully restored this set would be one heck of a conversation piece in anyone's den.
"black capacitors matter!". LOL
HOLY CRAP LMFAO DON! HAHAHA !!!
+Steven King 11:27 it's around there
"get in that cell, black capacitor"
It's that time of year as I watch this, BCM is perfect.
They don’t work either
I'm so glad to see some one still working on stuff like this
What a stupid design as you say, also imagine the extra power usage when only listening to the radio. Great to hear Chris on the background too. That tune amp is a pure beauty.
Power was dirt cheap, not an issue in those days.
I don't think the cost of electricity was much of an issue in the 50's, much less for the kind of people who would have been buying this TV set.
@@twizz420But the value of a watt is constant, and I can imagine the heat output from one of these making a room unbearable on a hot day.
“It’s got a huge burn mark right in the center”
Is what I got out of the last 30 minutes of this video.
It's always weird to me, hearing modern music on an old radio.
Still surprised that fm and am is still around?
Suchalongname Bythetimeyouaredonereadingthisitsover Not really, it's just weird to imagine how people 60 or 70 years ago would of reacted to modern rap or something like that, if they could've somehow head it. Makes me think about time travel, lol, :-)
Melissa0774 True I it's always good to see some old analog devices still getting signal
I picked up a 1951 Philco console Phono / radio last summer and I got it home and powered it up and I went through the Am band (nothing but talk and two OLDIES stations)Nothing weird. I switch to FM and (I'm in western Oklahoma) I hit 4 or 5 country stations, it's all good, then I hit the local hip hop station playing something like Black Eyed Peas or whatever I literally yanked my hand away like I had been electrocuted, lol. It seemed SO WEIRD! So yeah I know exactly what you mean!!
I received the same feeling, watching a trashy piece of television content, on a 1962 Panasonic that Shango66 refurbished. Shango66 rightfully made fun of the woman featured on this tube. "Escalaye!"
Where is part 3? I'm stuck binge watching!
if you didn't point it out, I would never have noticed he burn spot
Hi Shango066, I am enjoying your TV repair Videos a lot here, It brings back good old memory's of My Days at Grand TV way back in 1978 how ever I find it incredible to see you get these very old TVs from 1951 & stuff. We never got any thing this old at the TV shop I use to work at in Duluth MN back in 1978 But We did get a lot of 1967 RCA floor model TV sets in that needed the big silver caps replaced & We worked on lots of Zenith TVs as well & other brands. Most of the TV We would get at Grand TV were lots from the late 1960s & lots of color & B&W TV from 1970 & up to the mid 1970s & new late 1970s TV that had some defects That Grand TV fixed. We did have one old round color CTR TV come in that was an RCA TV & the Flyback was shot it started smoking When my friend Mike went to check the high voltage on it. the Flyback was no longer available & the owner did not want to have it fixed. Grand TV sold new 19" TV sets, The RCA XL 100 was one brand & Zenith all so as well. I sure wish I could meet you, But I live way up in north eastern MN But I wish I could hook up with you some how. I had a VCR Business on my own from 1987 till 2002 & at that point VCRs became to cheap to fix. It's so cool how you find these very old sets & get them all working. Now today even with the HD flat screen sets We have all kinds of very odd Makes & Zenith & other good name brands are not making TVs any more like it was in the olden days. Take care, Jerry C.
Man the that console is beautiful. I'm sure that was really spendy in it's day
LOL @ Push It, it was really moving that grill cloth. Man it's incredible what ten watts with the right speaker can do.
It shook my house
That thing deserves to be repaired. Interesting set.
Прелестный аппарат! Умели делать раньше красивые и надёжные вещи! Благодарю Вас за эту техноархеологию!
Your videos are great...you, uncle Doug and radionut have caused me to try my hand at repairing old tube radios...of course I started on a Philco 37-641 and am banging my head against the wall with low volume issues. I'll figure it out sooner or later...probably see you do something that will point me in the right direction.
Try bandersentv and DaveWM too! And felixthehousefreak. They are all friends...
be sure to redress new capacitors in blackface
F***n nice camera! Smooth 60 FPS motion. Love it!
It doesnt look natural
The best TV repair man in town.
+shango066 Hi, it's a new subscriber here. I've been watching your videos for years, but I ususally use TH-cam without logging in. Today, I've logged in after a long time, so I decided to subscribe right now. I also collecting vintage TVs and radios here in Hungary, and found very interesting to see these US made sets.
I like yours and Bob Andersen's channel as well in this topic. Two completely different approaches of restoration, Bob virtually rebuild his sets replacing all capacitors and most of the carbon-paste resistors, uses modern resistors and film capacitors, while you are just replacing the components essential to get a working set, and don't bother with checking all component values being inside their tolerance ranges. I also like to see the possible highest count of original components in my sets, so I also replacing just which are necessary to, and if I have to replace something, I am striving to use NOS components if possible. But I like Bob's approach also, and he frequently working on such old and/or bad condition sets that really deserves that level of care.
TV broadcasting started in 1957 here in Hungary, so we don't have pre-war sets, my oldest ones are from the early '60s, and they have a very high ratio of factory original components. Our first color sets were made in the mid '70s, only 2 type were made with tubes and delta-CRT, all the later ones were solid state and used in-line CRTs. They are very rare nowadays, unfortunately I haven't got any of them, I have just some B/W tube sets, and vintage solid state color sets from the '80s.
+mrnmrn1 Bobs approach is no doubt the right way to restore a vintage set. I like to get them working and verify no major defects before I go all they way. As you can see the burn spot on the CRT on this set makes it less describable and lower priority than many of the other sets I have that need to be restored. I am with you on keeping the maximum amount of original parts but capacitors are a major issue most of them time on sets this old. There will be follow up on this set but not right away.
first time I ever saw a capacitor smoking!
That TV sorta reminds me of my grandparents Dumont. Same 19" round metal CRT, and Mallory indotuner? Actually the TV sound subcarrier IF is about the same bandwidth or LESS than standard FM, so yeah, the indo tuner would work on FM. In fact my grandparents Dumont tuned FM between channels 6 and 7 along with the aircraft band (somehow got AM) and the 2 meter ham band. It even had a dual speed vernier drive and a slide rule dial that expanded the section between 6 and 7 to tune the FM band (complex gearing and dial string drive IIRC). 6AL7 eye tube poked in the middle of the dial.
Ion burn doesn't mean that the CRT had the wrong gun! There was a system that had a straight fire gun with TWO iron trap magnets, but if you didn't get those magnets set up just right you'd burn the screen. There was a diagonal cut inside one of the gun elements that directed the beam off to the side INSIDE of the gun, you can't see that well from outside of the tube.
I quote: "a 'slashed-field' gun was used and the G2 and first anode elements were cut diagonally to form a slant electron lens which caused the electrons and ions to be bent towards the neck and the double ion trap was used to first move the electrons slightly up and the second magnet to bring the electrons up to be aligned with the electron gun aperture disc. Apparently if a large magnet was used it would bend some of the ions up as well. Later the electron gun itself was bent towards the neck wall and this only required a single magnet trap to move the electrons up. This info is more clearly explained in The Cathode-Ray Tube by Peter Keller."
Those bumble bees were leaky 45 years ago when I started fixing televisions .
Robin Sattahip , same observation here. Bad capacitors in any tube set can, and do, destroy other associated components, some of which are almost impossible to obtain today. Best advice is to replace all of these paper capacitors and avoid destroying the other parts.
we should finish the set up this weekend. have to see if he got the extra caps.
Remember a Hoffman console TV in the basement of our Denver Colorado house when I was little.The Hoffman was OUR set and the brandnew metal "bucket" model Zenither was for Mom and Dad-Sometimes when a really good show came on-we all watched on the Zenith.The Hoffman we had had a green screen-kinda like an older computer monitor.I watched Mickey Mouse,Superman,Howdy Doody,and others on that Hoffman.Ours would have been like the one shown but didn't have the tuner or the TT.
Dumont made CRTs with straight guns for several years, they all had ion burns, the burn would be there even if rebuilt. My Stromberg Carlson (Dumont clone) has the burn, later 16" metal bell tubes had aluminized screens but they are kind of rare.
Nice camera. Very clear
The new camera is awesome!
This is a "split sound" TV. Instead of treating the sound carrier as a 4.5 MHz subcarrier that is picked off after the video detector, it has its own IF strip at 21.6 MHz. One disadvantage of this approach is that when watching TV, the fine-tuning would be absolutely critical. Mistune by a slight amount, and the sound will go bye-bye.
I put the Parallel "T" Bass Shaping Filter seen at 8:26 into a circuit simulator. That thing is a combination of a high pass filter and a 10 Hz notch filter. So no loudness or bass boost or anything like that. I wonder what that is good for.
you need to restore this one, just because of the rarity...
wow what a nice set
i wish we in holland had sets like that
hello
1marcelfilms hi
Philips are far better :-)
Without those diagrams it seem's it would be nearly impossible to fix. Wouldn't it?
Back in my day we had several of those old ass tv sets. I can't remember any of them that worked properly.
Keep working on it. The audio sounds very good on am and fm, and you do have a picture and sound which is remarkable.
Hoffman made the 1st commercial solar cells. Vanguard satellite was powered with Hoffman solar cells.
I love the resolution!
I like the beauty of the furniture. I would like to have it in working order if I had room.
P.S., you got stung by the bumblebee. ;)
Beautiful set. 5 years older than I am!
the base on this t.v. is dank, nice thump to it
That audio sounds amazing
Oooh, Look at the ion burn! Like that matters at this point
Video looks great even at full screen. Sounds is good too. I'd try to get that unit completely restored, record player and all. A fine example of early 50's "all-in-ones"! Oh by the way, you can't call the caps "bumblebees", then you'll offend real bumblebees. You'll probably just have to call them those "thingies".
That journey sounds perfect for a video game arcade from the 80's
Another great vid San-go
The CRT like the Bernie Sander's campaign is "feeling the burn".
haven't seen those old "breaded" resistors in a LONG time.
I could be stupid,but I just found me a Hoffman in pretty fair shape.. brought it up slowly with a variac just to see if the pic tube had any life, it did,and immeadiatly removed all power. being that it is a 1950 model pushing 70 years old, why would you not just replace all caps, all resistors, the start trouble shooting, this would include giving all pots and tuner a complete bath and checking all tubes to include mutual conductance values.
That's what I said.
If you are going to replace all components with modern Chinese ones, then why not throw the whole thing in the garbage and get a Chinese TV from Wal-Mart? The resistors are almost never bad, the capacitors are rarely bad enough to be the fault, and electrolytics of this era are rarely totally bad. Do you have no interest in getting the set running on as original components as possible?
@@gregorymalchuk272 The sand resistors always go bad and bumblebees short almost always. They already had a failed sand resistor and a bunch of bumblebees.
@@jussapitka6041
I've never had a sand resistor go bad on me, though most of the old paper capacitors are junk. That said, most of my stuff is running on original equipment, with minor repairs.
that's a hella nice snap on extension
It's got a huge burn mark in the center of the CRT. Oh wait, you let us know that about 12 times.
Interesting video. Thanks.
Será necessário uma boa limpeza nos contatos e uma substituição de componentes. Abraço
That's one bad ass sounding TV :)
Can stop laughing at the "cremate that tube real quick" line.
I am amazed at how good condition the service manuals that you are going through on your videos. Must be unused ones.
I remember as a boy our b+w TV was fixed by a neighbor. Could you reccoment a free good book to learn about tube TVs? I have restored many valve radios. I learn a lot watching your clips. Thank you.
Just looking at those capacitors makes me want a game of dominoes, or eat a pizza.
37:47 - What channels are broadcasting in analog nowadays?
+shango66 i like the way you make old CTR and vintage tv i have two old tvs that broken have a broke lamp i wanted to ask you to fix it but i live in NL
Call DirecTV and have them come over and service that box LOL
Good job you guy's (shout out to Chris71) It's still worth saving even though the CRT had Ion burn in the middle. Few of those old machines worked well (by today's standards). Yes, Those "Bumble-Bee's are junk, but you might be surprised how much naive guitarists are willing to pay for them on E-Pay. They were used in many old guitar amps of old. Many of the Bumblr's have a shorter life than those vertical canned electrolytics. IMHO, you should save the Hoffman from the dumpster. 'Shirley' it will be a great prop for the future movie business. 73'
I've seen ion burns worse then that. Generally, the burn will start out very small and grow.
Thanks alot.
Did this belong to the Sultan of brunie..grandisimo !!
AWESOME VIDEO!
camera seems pretty good.
Nothing personal, but I only give thumbs up to shango066 not shango006 with guest stars.
Coming soon: Hoffman Easy Vision wine cabinet
I'm curious about the TV tuner - is it inductively tuned? Also noticed the sound tuning is real sharp. Evidently this set doesn't use intercarrier sound. On those set you have to set the fine tuning to get sound and take what you get for the picture.
Come to think of it, do you actually collect the old electrical components you remove as part of your repairs?
I have all the stuff to build an amp like that but need a schematic and some time and a chassis. Man I even have a speaker ...
"Let's recap where we're at..." emphasis on recap. Cool unit, too bad it wasted so many electrons in radio mode.
Did really never properly experience the warm up and slow glow-in that happens. But it's telling of simpler times.
Ahh, the Hoffman.....I was hoping you'd get back to it. Just my two cents, but I'd fix it. I know the ion burn is a bummer, but it will still work for now....and later you might be able to find another crt for it. The caps in that think are junk, you might be better off just shotgunning them all at once.
I need this tv
Def Leppard and Journey sound great on anything!
tienen el poder que necesitaremos
only thing i see on the screen is a tripod and a biped
paper and electrolytic caps that is... might have left the micas if they were still not leaky.
Weak damaged CRT is a bummer. But my vote is fix it up. Never know when a tube might fall in your lap and besides what a nifty F&&king set. Craftsmanship inside and out. Is there the possibility of retrofitting a different more common CRT into this one? Anyway nice vid man!
did ya ask chris to help with the LCD replacement cable? if he knows anything about it...
+shango066 Are you never try to rejuvenate a tube? AFAIK, if a CRT (or any tube) is stressed only by heating, without applying bias, causes different type of degradation than normal use. Mainly cathode poisoning, which affects mostly the surface of the emitting material, therefore it may can be removed either with a delicate, low current rejuvenation. If I were you, first I would try to ground the cathode, to give the CRT an 'infinite' beam current, sometimes it's enough to burn away the poisoned layer of the emitting material, and burn the possible cathode-g1 bridges caused by the evaporation of the cathode material.
I don't understand why CRT rebuilders were used straight guns for originally tilted-gun CRTs. If tilted-gun assemblies were no longer available, why don't they aluminised the re-built CRTs before re-assembly? They had all the stuff for re-building a CRT, I don't think that the aluminising would be a big problem for them. I think they only need a rubber plug to the cutted-neck CRT, with a tungsten filament going through it, mount the right amount of high purity aluminium among the turns of the tungsten filament, then suck the CRT to high-vacuum with that rubber plug applied, warm the tungsten filament until white-glow to evaporate the aluminium, and that's it. Am I wrong?
+mrnmrn1 I can do that. Dont usually but I can.
But it's not your set is it! So let the man f it up and learn from it
I would have saved myself a lot of misery, and maybe saved that 150 ohm by replacing every cap in that entire set before I ever turned it on. It is not worth the chance with those old units.
new subscriber and i have a question do you sell some of the tv's you repair or no?
Sound realy realy hot gooood !!! WOW
Did you ever think of doing a third video for this TV?
I know that the last guys in the US that rebuilt CRTs went out of business a few years ago,but have you talked to people like arcademonitor.com or Pinball Medic who rebuild CRTs for old arcade video games? How is the CRT Rebuilding Project from the Early Television Museum coming?
Damn dude!
If I were you I would have a whole new modern TV with color. put in the cabinet . I would not go throught all the trouble tring to make that old TV work.
Is that your brother? Your voices are so alike! I love it.
Is electronic repair your job or hobby? What is your full time job?
Shame about the CRT ;-(, brighter than my old PYE!!
that song 27:42 what was the name again
why is the crt green? i have neber seen one like that
😮 No circuit boards!!
That's normal for TVs and radios of that age... Very few had PCBs back then
Not until sometime in the 1950s (i think) Saw a 50s Motorola radio with circuit boards.
00:18:00 Bien con esa válvula, en remover los contactos del zócalo. ✌👍📺📻
00:20:00
Good afternoon, please, you can't add subtitles in Latin Spanish. Thanks and regards from Buenos Aires, Argentina. And that smoke? Is it from the Flyback? What happened to the tension?
00:21:57 Excelente Sonido 🔈🔉🔊🔊🔊🔊
00:25:18 Buena alimentación de señal. To have capacitor de acoplamiento en buen estado?
00:28:28 Good TV 📺 is a channel Spanish ✌✌✌
IS FM OR TV?
What is tue model # of tye tube amp at 9:26?
What is the model of the amplifier?
Is that an econo tv from that era.
+David Okanagan
No, it's not, it was a fairly high end set for 1951 as it has built in AM/FM radio included, along with a record changer.
I don't think Hoffman ever did make anything that's considered low end.