Hi Tony, I know this is not very relevant to this but I had to say something. I'm an ex serving member infantry from the U.K. I got injured bad and had to be discharged from the army after 20years service. I have been meaning to Wright and say an almighty thank you too you sir. I was lost and didn't know what to do with my life till I came across your UA-cam videos. Basically what I'm saying is a massive thank you for getting me out of a rut and getting me in to something I now love. I have now repaired many stereo receiver and amplifies some small my latest been a rotel RA 1412. Sir I would like to thank you from the bottom of my heart for giving me a new lease on life.
How bad can it be? Spoken like every person before working on an SX-42 for the first time. Mine was a gift from my Dad, who bought it brand new as a teen. He gave it to me when I turned 15. I had it fully restored almost 4 years ago. It is a pure beast. Mine was built in Oct of 46, and thankfully I have accurate “before and after” schematics. No two are alike. Supposedly 10/46 was the first production run. Based on the front panel, the one you are working on is clearly a later run. Wishing you luck on this one!
You push something through the holes in the rear of the power connector, and the fuses come out the front....Heathkit and Johnson and others used those connectors.....
I remember my Uncle (who lived in the Adirondacks during the summer) had a (1960's vintage) wide-band/shortwave radio. I used to love to play with that rig..until I discovered FM and "underground rock" stations. Then I became a novice "audiophile".
Years ago, I restored an SX62, which is electrically nearly identical to the SX-42. It was one of the most maintenance intensive projects I have ever done. Not only did all the paper caps have to go, but the output transformer and filter reactor failed along the way. I had the output transformer professionally rewound, which resulted in better then original high frequency response. For the choke, I put a choke with similar specs in the original choke case to keep the original look. It's one of the best sounding tube receivers I have ever heard. I have two more waiting their turn on the bench.
38:59 you can see something lights up in the middle off the picture. Just above the shaft/bar and on the right hand side of the plate in that dark area. You can set the playback speed at 0.25x to see it a bit easier. Can’t wait to see part two, cheers!
I trust this is a work of 'love' and not a job paid 'per hour'.. If the latter, the cost would exceed the value of the receiver! Yet, a fun project challenging the brain and knowledge. Keep at it!
The labor required of all radio restorations, in my experience, exceed the value of the devices I work on. It's just a fact of life in the throw-away society we've made for ourselves. I do it because I love it, not because I'm trying to make money at it.
I have rebuilt 3 SX99s, an SX71, and am about 50% through two 100s and I have thought about doing one of these. You have convinced me to stay away from this model until I am better at it and am ready to disassemble totally. What a jammed mess! The Antenns/RF/ osc box switch sections remind me of a Borg vessel if you are a star trek fan
A really enjoyable video Tony, I wonder how many other viewers were trying to look around behind the components for the fault. Made me laugh at myself when I realised what I was doing. Look forward to part two. Stay safe!
Phil from www.antiqueradio.org has this same receiver and had a shorting issue when switching from AM to SW. Turned out a leaky cap caused one of the wafer switches to arc and carbon track causing a short when changing bands. This looks to be a similar issue. Phil had to scrape all the carbon out and fill in the damage section of the wafer to remove the short. I remember reading about this years ago in his restoration article on this receiver. Apparently it's a common issue with the SX-42.
It's like watching the tiger scoping out the prey, Tony's on the hunt and all that's missing is the voice over guy to guide us through the actions and thought process of how he takes down the beast, this is the world around us! Fascinating.
Very interesting, Tony. Looking forward to the final repair and alignment on this fine old receiver. A question if I may: You state at 44:20 that the cathode caps on both 6AG5s "have braided leads to help with image rejection on the higher FM bands." I've not heard that before, though I'm still new at radio restoration. Can you explain why braided leads on a tube (or is it the cap?) would help with image rejection on FM? Thanks for an excellent series!
The intertwining of the wires in the braid will cancel out higher frequency noise in AC (not DC). It acts like a filter similar to the way an inductor cancels out higher frequencies. In this application it seems to be filtering out noise from the chassis. This video is about cables, but the principal is the same for noise cancellation. ua-cam.com/video/DC0s6KqQz3g/v-deo.html
I had a similar problem in one of my ham transceivers, on the TX driver coil switch deck there was carbonising between two rivets on the switch rotor. Diffifult to remove the bad deck from the tight stack of switches, I had another switch from which the rotor became a donor. I saw a glimmer of spark and smelled the burnt bakelite
Almost wet myself when you said "embalmed in deoxit", I could just picture some bright spark saying "it's got to be the switch, more deoxit" Otherwise, what a can of worms. In these cases I'm almost tempted to just buy them a new radio to save myself from hours of grief.
You are better at resisting the "OK, this is too messy, I'm going to tear it all out and start over" temptation than I (hardware OR software.) But the smart money is on "No smoke; ship it!."
Have had a similar challenge with a restore of an SX 101 MK3 which had product detector mods as well - to determine what model/schematic was (Mk1, 2, 3 or 101A - meanwhile a lot of fun and great old engineering
The lines in the 6V6 inner "shadow" are caused by the edges of the mica spacers when the tube is constructed. That is done for rigidity of the spacer and prevents, or mitigates microphonics....
I know what those are. The lines in this one were zig-zagged. It was baked. The glass was also cracked. You could feel it with your fingernail (well, maybe not through the monitor, but...)
@@xraytonyb Ah ha, that's why I couldn't feel that crack in the glass! I would have to come back and watch the video again after I have dropped my phone and cracked the screen to feel it hahahaha ROFL 😂
About that output valve. I've seen lots of valves with those marks caused when the locating spikes on the mica mountings are slid into the glass tube during manufacture. I can't tell if this is the case here.
Just wondering if the Radio had been rebuilt to use vacuum tubes that used a B+ of 12V (The tubes that were developed in 1961 for when transistors of the day were not ready for prime time) so that people can fix the unit themselves and not get electrocuted and wind up in a early grave.
Probably the weakest point on the Hallicrafters are the flimsy band switches, great detective work, Tony! Looking forward to part 2. Silver mica disease can also be cumbersome, but I'm sure you'll win out. BTW I have one of these buried in my basement I haven't tried to power on yet and I've had it at least 15 years! Happy fourth...........................
john sampson , Suggestion. DON'T "try it." Go watch Paul Carlson's posts on Patreon, "Mr Carlson's Lab." Study his restoration videos, as the latest ones are too short and don't have the depth of some of the older ones.
After watching this video it has made me want to get an sx 42 in the worst way. At first I thought why not a 43 which was made on my birth year. Then I found all the reductions put into it compared to the 42 and since the 42 was made till 48 it is what I want to rebuild. Then looking at all the problems Tony ran into I'm not sure I am up to it. Will try though or straight to the FT 101. I consider these two radios the best of class through time. Just as an earlier Hallicrafters SS 28.
This thing is 73 years old. Built to top specs of the day. Face designed by Raymond Loewy. Deserves to be restored and aligned.Time to get to work. Happy hunting.
Good job Tony finding this before more tubes go bye bye. Of course with not working what do you think was first here. I mean the tube may have been first. Or the cap?
I really want an SX42 My uncle had one I inherited but someone took it from me. Was nice to see the inside had no idea how many gangs on the tuning capacitor
These digital meters will jump around if there is a lot of Inductance. If you use an old analog meter like a Simpson 260, the Ohms reading will be steady.
Tony, Writing a duplicate on this newer video. I have a question outside of your video box... but then you inspired me to pick up a scope, meter, and remember my 1970 electronics... Need your help or contact to locate an BSR EQ-3000 manual, as trouble shooting the circuitry this one is baffling me for 2+ months and I really hate asking you this question. If possible, please help. John
I was taught that the first tests should be done with the eyes and the nose. In other words, have a good look round for obvious bad joints, scorch and burn marks, blown caps and the like. Then have a good sniff around for burning smells. Of course all this is done with a unit unplugged.
Measuring R from plate to plate only tells you that you have R. If you measure from Ct to each plate you can compare the two windings. Often with faulty/blown O/P valves one leg can be open or have shorted turns which will only show up with a comparison. Also it's common on over stressed transformers to have resistance leakage either to the secondary or to the frame which would give this exact symptom. I know this wasn't the case here.
jonka1 , Thought about that but forgot to put it in my blast above. He might want to measure the impedance as that will tell you more about the transformer than its resistance. de KQ2E
Was good sleuthing. Will be interesting to see the end result of this tenth step. These old hallicrafters seem to be a bear. Do you shotgun cap the whole section?
Good work. Though one. I wonder why Halicrafters used this type of switch, they are known to suck moisture from the air. This one was obvious hosed down with deoxit spray and accumulated a lot of dirt over years wich probably worsened the problem. I guess it will not be the only spot on the switches that it will make trouble in the future. They should have used ceramic switches instead, it was a very very expensive receiver when new.
No point to repair the 6V6 push-pull AF section since tube is hardly obtained in year 2023. As I want to fix it, replace the whole AF section with a few dollar cost AF module IC shall do and last forever, not like 6V6 has a life about 1000 hours. Just need to modify volume control into lower value and tone control RC circuit ( modify with bigger capacitance and lower resistance) to meet the IC AF amplifier requirement. Add a low voltage power source like 12V 2A small size AC-DC converter to support a 3W AF module, costs just a few dollar, can be found from eBay. Rectifier tube can be fixed by parallel 1N4007 across both plate and cathode, cut away the 5V power source for it. 150V regulator tube can be replaced with 150V zener diode 3W. Be sure to modify the resistance value to meet the zener diode requirement. Or make a constant 150Vdc power source circuit.
I had one of those (similar to that one) and my brother in law talked me out of it. It shocked me so bad I flew backwards about 7-8 feet. My arm was numb for a week.
Hi Tony, I know this is not very relevant to this but I had to say something. I'm an ex serving member infantry from the U.K.
I got injured bad and had to be discharged from the army after 20years service.
I have been meaning to Wright and say an almighty thank you too you sir.
I was lost and didn't know what to do with my life till I came across your UA-cam videos.
Basically what I'm saying is a massive thank you for getting me out of a rut and getting me in to something I now love.
I have now repaired many stereo receiver and amplifies some small my latest been a rotel RA 1412.
Sir I would like to thank you from the bottom of my heart for giving me a new lease on life.
How bad can it be? Spoken like every person before working on an SX-42 for the first time. Mine was a gift from my Dad, who bought it brand new as a teen. He gave it to me when I turned 15. I had it fully restored almost 4 years ago. It is a pure beast. Mine was built in Oct of 46, and thankfully I have accurate “before and after” schematics. No two are alike. Supposedly 10/46 was the first production run. Based on the front panel, the one you are working on is clearly a later run. Wishing you luck on this one!
You push something through the holes in the rear of the power connector, and the fuses come out the front....Heathkit and Johnson and others used those connectors.....
I remember my Uncle (who lived in the Adirondacks during the summer) had a (1960's vintage) wide-band/shortwave radio. I used to love to play with that rig..until I discovered FM and "underground rock" stations. Then I became a novice "audiophile".
I saw the flash! ~ @ 39:00 Little tiny flash deep inside that 2nd from left large section the camera is focused on.
matran47 , I saw a TINY flash at the bottom left of that second bay at 38:59, but who knows.
New drinking game. Anytime XrayTony or Mr. Carlson says OUTSIDE FOIL you have to drink.
You'll need more than a gallon of beer.
Years ago, I restored an SX62, which is electrically nearly identical to the SX-42. It was one of the most maintenance intensive projects I have ever done. Not only did all the paper caps have to go, but the output transformer and filter reactor failed along the way. I had the output transformer professionally rewound, which resulted in better then original high frequency response. For the choke, I put a choke with similar specs in the original choke case to keep the original look. It's one of the best sounding tube receivers I have ever heard. I have two more waiting their turn on the bench.
38:59 you can see something lights up in the middle off the picture. Just above the shaft/bar and on the right hand side of the plate in that dark area. You can set the playback speed at 0.25x to see it a bit easier.
Can’t wait to see part two, cheers!
Good eye.
The flash did show on the video. Cameras are good tools. Appreciate the content you provide.
Tony you are the Hercule Poirot of radio restoration. A truly great detective. I enjoy your systematic thought.
I trust this is a work of 'love' and not a job paid 'per hour'..
If the latter, the cost would exceed the value of the receiver!
Yet, a fun project challenging the brain and knowledge. Keep at it!
The labor required of all radio restorations, in my experience, exceed the value of the devices I work on. It's just a fact of life in the throw-away society we've made for ourselves. I do it because I love it, not because I'm trying to make money at it.
Excellent commentary during the video. Allows me to understand your problem solving strategies. Great job!!
PS- Tony, hope and pray there are no issues in the bandswitch. If so, we will see you on Part 20- kidding, sort of...
Arthur's Hallicrafters Kitchen & Audio Lab , Just open a "Hallicrafters switch replacement center" for all the poor "victims."
I have rebuilt 3 SX99s, an SX71, and am about 50% through two 100s and I have thought about doing one of these. You have convinced me to stay away from this model until I am better at it and am ready to disassemble totally. What a jammed mess! The Antenns/RF/ osc box switch sections remind me of a Borg vessel if you are a star trek fan
A really enjoyable video Tony, I wonder how many other viewers were trying to look around behind the components for the fault. Made me laugh at myself when I realised what I was doing. Look forward to part two. Stay safe!
I’m glad there’s a part two as part one is just 1 hour. 😜
Phil from www.antiqueradio.org has this same receiver and had a shorting issue when switching from AM to SW. Turned out a leaky cap caused one of the wafer switches to arc and carbon track causing a short when changing bands. This looks to be a similar issue. Phil had to scrape all the carbon out and fill in the damage section of the wafer to remove the short. I remember reading about this years ago in his restoration article on this receiver. Apparently it's a common issue with the SX-42.
Seems like the SX-42 has a lot of common issues ;)=)
It's like watching the tiger scoping out the prey, Tony's on the hunt and all that's missing is the voice over guy to guide us through the actions and thought process of how he takes down the beast, this is the world around us! Fascinating.
Very interesting, Tony. Looking forward to the final repair and alignment on this fine old receiver. A question if I may: You state at 44:20 that the cathode caps on both 6AG5s "have braided leads to help with image rejection on the higher FM bands." I've not heard that before, though I'm still new at radio restoration. Can you explain why braided leads on a tube (or is it the cap?) would help with image rejection on FM? Thanks for an excellent series!
The intertwining of the wires in the braid will cancel out higher frequency noise in AC (not DC). It acts like a filter similar to the way an inductor cancels out higher frequencies. In this application it seems to be filtering out noise from the chassis. This video is about cables, but the principal is the same for noise cancellation. ua-cam.com/video/DC0s6KqQz3g/v-deo.html
Really enjoying the detective work on this Tony - thank you.
“It’s next to the hot resistor, which gets hot” - 🤣
Finding that terminal which was shorted through the PCB by carbon buildup, was a master stroke
That radio looked you right in the eyes and said, "Umgwanakikbuti"! That's a tough one for sure.
I had a similar problem in one of my ham transceivers, on the TX driver coil switch deck there was carbonising between two rivets on the switch rotor. Diffifult to remove the bad deck from the tight stack of switches, I had another switch from which the rotor became a donor. I saw a glimmer of spark and smelled the burnt bakelite
Almost wet myself when you said "embalmed in deoxit", I could just picture some bright spark saying "it's got to be the switch, more deoxit"
Otherwise, what a can of worms. In these cases I'm almost tempted to just buy them a new radio to save myself from hours of grief.
You are better at resisting the "OK, this is too messy, I'm going to tear it all out and start over" temptation than I (hardware OR software.) But the smart money is on "No smoke; ship it!."
Have had a similar challenge with a restore of an SX 101 MK3 which had product detector mods as well - to determine what model/schematic was (Mk1, 2, 3 or 101A - meanwhile a lot of fun and great old engineering
39:25 there was a flash, Tony.
Indeed there was; very small, in the background.
I saw it too, but my clock is reading 38:59.
I always test the tubes first. Saves a lot of time.
Once the smoke comes out, it's hard to put it back in.
The lines in the 6V6 inner "shadow" are caused by the edges of the mica spacers when the tube is constructed. That is done for rigidity of the spacer and prevents, or mitigates microphonics....
I know what those are. The lines in this one were zig-zagged. It was baked. The glass was also cracked. You could feel it with your fingernail (well, maybe not through the monitor, but...)
@@xraytonyb Ah ha, that's why I couldn't feel that crack in the glass!
I would have to come back and watch the video again after I have dropped my phone and cracked the screen to feel it hahahaha ROFL 😂
About that output valve. I've seen lots of valves with those marks caused when the locating spikes on the mica mountings are slid into the glass tube during manufacture. I can't tell if this is the case here.
Just wondering if the Radio had been rebuilt to use vacuum tubes that used a B+ of 12V (The tubes that were developed in 1961 for when transistors of the day were not ready for prime time) so that people can fix the unit themselves and not get electrocuted and wind up in a early grave.
Very enjoyable Tony, looking forwards to part 2.
We can see the spark on the rotary selector already @38:58, just before you say "I didn't see anything".
Probably the weakest point on the Hallicrafters are the flimsy band switches, great detective work, Tony! Looking forward to part 2. Silver mica disease can also be cumbersome, but I'm sure you'll win out. BTW I have one of these buried in my basement I haven't tried to power on yet and I've had it at least 15 years! Happy fourth...........................
john sampson , Suggestion. DON'T "try it." Go watch Paul Carlson's posts on Patreon, "Mr Carlson's Lab." Study his restoration videos, as the latest ones are too short and don't have the depth of some of the older ones.
38:59 The moment of the spark :
ibb.co/KzCgqS7
Right after the spark :
ibb.co/2vzksMg
After watching this video it has made me want to get an sx 42 in the worst way. At first I thought why not a 43 which was made on my birth year. Then I found all the reductions put into it compared to the 42 and since the 42 was made till 48 it is what I want to rebuild. Then looking at all the problems Tony ran into I'm not sure I am up to it. Will try though or straight to the FT 101. I consider these two radios the best of class through time. Just as an earlier Hallicrafters SS 28.
The SX-42 is an amazing radio. It can also be a nightmare to service, especially if someone worked on it before you.
This thing is 73 years old. Built to top specs of the day. Face designed by Raymond Loewy. Deserves to be restored and aligned.Time to get to work. Happy hunting.
In the middle section, on the right above part 448165, you can see a tiny cloud of smoke between minutes 39:07 and 39:08. Only takes a second!
Looks like the notorious SX-42 bandswitch heaven.
Good job Tony finding this before more tubes go bye bye. Of course with not working what do you think was first here. I mean the tube may have been first. Or the cap?
Always enjoy watching new *video*.
:)-
Cheers,
The guy who recapped it sure loved his orange drops!
You have the patience for this. Congrats. That was a rare failure.
@28:35 those baby tubes are so cute!!
YES there is a small flash in that area, from back in, its on the vid . when you thought it was your glasses. its tiny. John KC2AGT
I really want an SX42 My uncle had one I inherited but someone took it from me. Was nice to see the inside had no idea how many gangs on the tuning capacitor
Super good find on the short.
These digital meters will jump around if there is a lot of Inductance. If you use an old analog meter like a Simpson 260, the Ohms reading will be steady.
24:52 When the camera kept zooming, i thought that the black hole of the earth pin was going to suck in the camera :-)
Real basket-case there, Tony.
And to think, you do this for fun! :)
Those damaged tubes “had a lot on their plate?” ...
Tony, Writing a duplicate on this newer video.
I have a question outside of your video box... but then you inspired me to pick up a scope, meter, and remember my 1970 electronics...
Need your help or contact to locate an BSR EQ-3000 manual, as trouble shooting the circuitry this one is baffling me for 2+ months and I really hate asking you this question. If possible, please help. John
I was taught that the first tests should be done with the eyes and the nose. In other words, have a good look round for obvious bad joints, scorch and burn marks, blown caps and the like. Then have a good sniff around for burning smells. Of course all this is done with a unit unplugged.
Stephen Cook , The list goes on. But it STARTS with a general NEW recapping with ALL the caps removed, INCLUDING the IF cans. de KQ2E
Measuring R from plate to plate only tells you that you have R. If you measure from Ct to each plate you can compare the two windings. Often with faulty/blown O/P valves one leg can be open or have shorted turns which will only show up with a comparison. Also it's common on over stressed transformers to have resistance leakage either to the secondary or to the frame which would give this exact symptom. I know this wasn't the case here.
jonka1 , Thought about that but forgot to put it in my blast above. He might want to measure the impedance as that will tell you more about the transformer than its resistance. de KQ2E
Looking forward to part 2...!
Was good sleuthing. Will be interesting to see the end result of this tenth step. These old hallicrafters seem to be a bear. Do you shotgun cap the whole section?
these never had mains fuses hope you fitted one
Good work. Though one.
I wonder why Halicrafters used this type of switch, they are known to suck moisture from the air. This one was obvious hosed down with deoxit spray and accumulated a lot of dirt over years wich probably worsened the problem. I guess it will not be the only spot on the switches that it will make trouble in the future. They should have used ceramic switches instead, it was a very very expensive receiver when new.
No point to repair the 6V6 push-pull AF section since tube is hardly obtained in year 2023. As I want to fix it, replace the whole AF section with a few dollar cost AF module IC shall do and last forever, not like 6V6 has a life about 1000 hours. Just need to modify volume control into lower value and tone control RC circuit ( modify with bigger capacitance and lower resistance) to meet the IC AF amplifier requirement. Add a low voltage power source like 12V 2A small size AC-DC converter to support a 3W AF module, costs just a few dollar, can be found from eBay.
Rectifier tube can be fixed by parallel 1N4007 across both plate and cathode, cut away the 5V power source for it.
150V regulator tube can be replaced with 150V zener diode 3W. Be sure to modify the resistance value to meet the zener diode requirement. Or make a constant 150Vdc power source circuit.
Great channel 👍
Well there's your problem, Tony! You have the outside foil ends facing the wrong way...
What a nightmare design, the designers need to be brought back from the past and slapped with a wet fish lol.
Just as punishment :-D
looks like a fuse plug from what i see
Good job sniffing out those problems
Hey nice power meter anyway you could send me a copy of the schematics I would love to build one for my work bench
Tony, I'm 64 years old; I've NEVER seen a 500-ohm or 5000-ohm speaker! (30:20)
Young whipper snapper!
@@erin19030 , Me, too... LOL I've just turned 79 and would LOVE to start over at ONLY 64!
I had one of those (similar to that one) and my brother in law talked me out of it.
It shocked me so bad I flew backwards about 7-8 feet.
My arm was numb for a week.
N. B. Job had WAY too much patience. Most annoying story in that book.
its at 38:59
0:14
9:00