As some tips, I drove myself crazy one time working on my Swan 1011 tube radio. My trusty mutual conductance tube tester showed all tubes were good. But they weren’t! My Elmer took it and subbed a tube that fixed my problem. Then he swapped a pair the radio already had and fixed the problem without replacing any tubes. One tube was used in an audio circuit and an RF as well. Also many of those IF cans have bad silver-mica capacitors inside of them that can be replaced. So you can repair them. That paint problem is a pain! Usually they have an off-white paint. Sometimes I’ve managed to get it loose with a steel Allen wrench. Then I’ve used a plastic one. But many times that results in a broken slug that must be replaced. PITA!
I got one of these for my birthday in December of 1978, along with a co-OP between me and my local channel club for a Taylor Grand Slammer .64 wave ground plane and 40 ft push up pole. Then got a D-104 for Christmas! Happiest kid ever, and I had more fun with that rig than you can imagine. Adjacent channel rejection was great, as I had two operators within 2 large blocks that didn't interfere with my operation unless they were 2 channels away. Later replaced the rig with another T-240D, and still love it! Thanks for the review... great information!
Nice to see someone who is knowledgable and through who actually cares enough to do repairs the right way. I see from your videos you do more than CB repair..You have the Only CB repair content that I dont call BS on by the second video.. I have found hours of intertainment on your channel..Nothing but Respect.. Hey at least those IF cans have sealed mica caps no silver mica disease... Really cool old radio .. I use Joint Army Navy tubes where ever possible..
Without a doubt a blessing they don't have the built in silver mica caps built into the base of the IF transformer. Lot's of early Brownings have gone to the grave because of that.
Owned the 123b is a terrific rig. If you're looking for a tube rig, and don't operate above 23 don't hesitate to bid on one. They sound great (I used a +2) and receive very nicely. Thanks Mike.
Awesome video I wish I had time to make them myself but I'm so swamped I can't believe the amount of people that are sending these in to get restored. I have 2 shelves full and got 4 more in today it's crazy. Anyway you do a great job take care.
It was so awesome to hear the receive in this classic tube radio, especially your demonstration of the tone control and squelch. Solid sounding tube fidelity from that little box. Had one available locally and didn't buy it. Now this has truly helped me make my mind up to purchase one.
I really enjoyed seeing this your valve tester I imported a similar model from the USA and installed a 230/110 step down transformer. Your tube tester are much cheaper than buying in the UK
Excellent video o tube radios. Not seen any mic plugs like that for years. i have one on my CB, it came with it fitted to a coffin mic. I did have a few as spares, but he stopped when the CB craze faded here, so I have no idea where he got them from. there is no manufactures name on them either. But like everything else, the stamped out tube for the mic pins are cheaper to make and easier and this is what they go for. Quality these day are sadly rejected for cost. Accountants run the world..... :-(
There ya go, now the light works. I see these radio's come up for sale a lot on Ebay, the 23 channel and the 40. Most of the ones I have seen were in great condition. I nearly bid on one of them, but I found out that they don't have SSB. I only own radios that have SSB as I like to do DX when skip is going on. I have a Stryker 955 HPC and a classic Galaxy 93T in mint condition, love both of these radios.
At 1:12:17 -- my understanding is the Foster Electrical Company of Japan created that plug in the 1970s as a copy of the larger Amphenol version, but Foster ceased manufacturing them circa 2011. Dunno where to get plugs with machined pins, but Switchcraft makes them with cable strain relief springs.
Good videos wish i had time to post some but im always so busy with repairs. These are very good built radios i have also been servicing them for years and have several of the 123 and 240D still in the original unopened boxes as well as dozens of tube Messengers. Keep up the good work.
Great video Mike,we dont see cb kit like this much in UK,one of the main reasons 455khz filters fail ,can happen by applying DC to the filter,either a bad coupling\decoupling capacitor on the IN\OUT of filter or No caps at all!,filters can get destroys be DC applied to the 455khz Ceramic filters over time,another well known modern brand had this issue on HF rigs. Wondering if this radio would take a Murata 455-HT filter as a upgrade? You mention the squelch,Ive seen these effect on Vintage CB Hts of 60/70's can do similar thing with squelch. Rob 73's
I have that same radio. I also have a colt 40 channel midnight special that looks just like it internally. I’ve got another one that’s a Shakespeare I believe that uses that same or similar chassis.
I think you'll be able to fine tune the radio , If you could loosened the IF transformer cores from top and the bottom sides separately. Nice informative video.
I just remembered I had another radio with a very similar chassis to that maybe identical I believe it was also a Robin and it had a narrow rectangular window in the front and a little tube behind it and it looked like a green bar graph that came together as you talked I can’t remember the model of it it was a 23 channel though. It was kind of similar to a magic eye tube but it was a bar graph.
James Bowie Thanks I’m glad you said That I couldn’t remember the model after you said it I searched it on eBay and I just bought one for 50 bucks. I’ll add that to my collection.
When you say this radio is PLL synthesized, are you talking about phase locked loop? I see the switch going to the PLL board so it made me think of my J.C. Penney's phase locked loop radio that I modified with extra channels above 40 and below 1. Back in the day (mid 70's) I had the very same Hickcock tube tester when I used to repair TV's.
I wish you could go through my yellow Robyn. I’d love to use it. It sounds muffled on Receive and transmit. and it’s weak. Kind of seems like maybe it’s slightly off frequency also. On the other hand at least it looks brand new.
Just found your channel a few weeks ago. Brings back some memories and nightmares too. How I survived the Golden Screwdriver era I don't know. So many ruined radios back in the day that people just tossed. Makes me want to cry sometimes. I may have missed it in the video but what does the Range Expand switch do? For the life of me I am drawing a blank.
Good point about the longevity of vacuum tubes. in my experience unless it is a tube that is doing hard work in the circuit such as RF finals or audio output tubes in the course of it's lifetime they just rarely go bad all other things being equal. I think the myth of tubes being faulty was promulgated back in the 1950's and 60's drug store tube tester era. Possibly even by the manufacturers themselves. Those testers always read "Weak" or "Replace" The unknowing weekend TV repair guy would buy new ones only to find that the new tube didn't fix his TV. I wonder how many perfectly good 12AX7's that are fetching precious metal prices today ended up in the garbage due to these testers. I have tubes in radios here from the 1920's and 30's that are still working just fine. ATB Doug.
Great radio,had one .hope you can fix it for owner .I like metal film resistor for repacements,any chance you no where I can buy those type of 455 hrz IF cans from ,They should work on vintage a m radios right anyone .
Mike do you possibly have a email address or phone number im looking for a good 10k ohm potentiometer wirewound 10 to 25 watt! My email is pdegroff53@gmail.com. thanks if possible!
@@1OFGODSOWN Thanks. I may be possibly playing with fire here but I used a very minute amount of acetone and ran the slug up and down a ways as soon as it loosend. worked well and didnt seem to melt the plastic tube. I have De-oxit but its the D5
@@peterdegroff1013 Your best bet would probably be Ebay for new old stock - www.ebay.com/itm/Ohmite-RES10K-Rheostat-Potentiometer-Wirewound-12-1-2W-10K-Ohm-035A-Model-E-NOS/322642564470?epid=1411853773&hash=item4b1efed576:g:i4wAAOSwAxJZ0n2N:sc:USPSPriority!33404!US!-1 That's not exactly an easy or cheap potentiometer to find.
Man I wish I had that schematic. I have an older Robin I can’t remember the model but it’s the same chassis but it’s a green 23 channel and it has the magic eye type tube as a modulation indicator. It’s like a bar graph. I need the schematic to see how the power cord wires I’m thinking it should be the same as the yellow Robin but I don’t know and I’m scared to plug it up.
Well you can clean the tube and pins it's probably been sitting in a wet box for many years, you can clean the pins with a fiberglass eraser pen or a pencil rubber the blue end or a bit of steel wool. Will isopropanol loosen the paint on the rf cans? Usually it dissolves paint very well you might find it will dissolve the paint and you should be able to turn it easily. I don't think isopropanol will melt the plastic tube I've clean plastic tubing with isopropanol and never noticed it melting, are those capacitors original I would have thought they would have had Mica capacitors probably been changed? I think using Surface Mount capacitors is better solder to a piece of wire bent in a loop as a heat dissipator. you can place them on the bottom, those film capacitors will get interference I would have thought being so close to the inductors. I would have thought the RF can next to the transformer would cause problems, it's only aluminium I would have thought they would have used still here! would be better. I don't know how you would defeat the interference from the coil being so close grounding is enough? and managed to tune it in properly. Is it an issue?? Would you get a better response having a still can here from the receiver. Why is the jumper wire put in there then, what is the benefit in the first place of the wire mod. You might want to try Advanced audio they might have those plugs? they make high quality studio microphones a Canadian family owned business.
Instant On. I thought that was only a vintage TV thing. It was advertised as 'Instant on' , no waiting for the warmup. Kept tubes partially warm. Remember from old TV repair in high school. Eat lots of electric as well. Yea should be labeled stand by and on then a fully off hard switch.
No, still has factory original tube in it. Increasing output in any radio is a bad idea. Radios were not designed to do "more power" and trying to do so does nothing but stress the power supply. In a tube radio that's a good way to burn up the transformer. Ask anyone who had to pay to get a power transformer replaced because they had their radio set up for "more power" if it was worth it. They will quickly tell you no.
Question: Why did you replace the 3 electrolytic caps with film caps? Those weren't non-polarized caps as you described. Just curious as I'm restoring a T240D myself.
If your referring to the .1uF Atlas oil capacitors they are absolutely NOT electrolytic. They are non polarized aluminum capacitors. The black line on them does NOT signify the negative end. The line on a non polarized capacitor signifies the outer foil or can.
Onan Robin what is that little yellow diode by that resistor had a little burnt spot on it mine's broken half a little dial with the yellow tip on it do anybody know the volume of that
Sir I have one of these The receive was loud and went in and low bot not out thought might been dirty potentiometer but not I can hear the skip on six but volume wide open to hear it
Hi sir, I recently acquired a yellow bird and my receive is absolutely perfect however my tx is not !!! It is only pushing about a 1/4 of a watt, I have replaced the 6ba6 tubes and no go, the radio is in extremely clean condition and I would love to repair it do you have any suggestions on where to start? Possibly a capacitor or somthing is there anything common that causes this on this model ? 🤔
If it doesn't transmit or receive you may be having a problem with the solid state synthesizer circuit. Check to see if you have proper output from the synthesizer circuit at the correct frequencies.
Too bad users are always so hell-bent on modifying these classics. That never ends well. The first thing I do when acquiring these radios on a hamfest is bringing it back to factory-original condition. That's when they work the best. In that regard, the T-240D Yellowbirds that I have worked on/owned always had a low-cost Murata ceramic filter rigged in between the IF stages. The one in your video has the mod too, I can see it clearly (the small black plastic cube). I assume there once was a particular CB butcher who offered that "improvement" service for sale. As a result, the radio's IF passband is completely screwed up and the receiver will sound tinny. The first thing I therefore do when getting this radio is to remove that ceramic filter, restore the circuitry back to original condition and re-align the surrounding IF filters to their proper 455kHz setting. This radio from the factory has FOUR coupled IF filters (that is eight 455kHz LC tanks, 16 poles) which is more than the average vintage communication receiver which normally has 3 coupled IF filters. So there is absolutely no need for this ceramic filter. Cheers.
The ceramic 455kHz filters were factory in the later Panasonic tube type chassis. I think it was a huge improvement because it narrowed the passband. They were much less prone to adjacent channel bleed over like the earlier models.
The three T-240Ds that I found to have this ceramic filter installed were clearly "upgraded" in a later effort, not by the factory but by a third party. That could be seen by the sloppy solder work and the fact that the ferrites in the IF filters had been retuned, which cracks the white paint that the factory had applied to prevent loosening of these ferrites. And as I mentioned earlier, the receiver audio response significantly improved (for all 3 radios) after returning it all to factory state. I have never heard of, or seen this particular Japanese tube chassis being equipped with this ceramic filter on other radios from different brands (as you know this chassis was used for many other radios like Gemtronics and T-berry). So I don't know what to tell you but I doubt the factory applied these filters, sorry.
@@LifeIsTooShortForQRP I guarantee you the ceramic filter board is factory. How do I know, it's in the SAM's manual. Manufacturers sent their radios straight to SAM's. Actually the SAM's schematic shows the ceramic filter and separately shows what they call "alternate circuit" which is the earlier version. I think I have only ever seen one 240 that didn't have it. Every other 240 I have seen has the ceramic filter board.
Great stuff! I found a T123-B brand new unused in original box a few years back. Story and photos here: www.pd2h.nl/barn-find-at-the-ham-radio-flea-market/
Anybody ever seen a version of these Japanese clones with RED covers? Maybe a Kris 40? I've only heard rumors but have a set of red covers that came off a radio I never saw or had-and I've had just about all of them. Looked like factory paint to me.....
As some tips, I drove myself crazy one time working on my Swan 1011 tube radio. My trusty mutual conductance tube tester showed all tubes were good. But they weren’t! My Elmer took it and subbed a tube that fixed my problem. Then he swapped a pair the radio already had and fixed the problem without replacing any tubes. One tube was used in an audio circuit and an RF as well. Also many of those IF cans have bad silver-mica capacitors inside of them that can be replaced. So you can repair them. That paint problem is a pain! Usually they have an off-white paint. Sometimes I’ve managed to get it loose with a steel Allen wrench. Then I’ve used a plastic one. But many times that results in a broken slug that must be replaced. PITA!
I got one of these for my birthday in December of 1978, along with a co-OP between me and my local channel club for a Taylor Grand Slammer .64 wave ground plane and 40 ft push up pole. Then got a D-104 for Christmas! Happiest kid ever, and I had more fun with that rig than you can imagine. Adjacent channel rejection was great, as I had two operators within 2 large blocks that didn't interfere with my operation unless they were 2 channels away. Later replaced the rig with another T-240D, and still love it!
Thanks for the review... great information!
This was always my favorite configuration for a transceiver. Best of both worlds...
Nice to see someone who is knowledgable and through who actually cares enough to do repairs the right way. I see from your videos you do more than CB repair..You have the Only CB repair content that I dont call BS on by the second video.. I have found hours of intertainment on your channel..Nothing but Respect.. Hey at least those IF cans have sealed mica caps no silver mica disease... Really cool old radio .. I use Joint Army Navy tubes where ever possible..
Without a doubt a blessing they don't have the built in silver mica caps built into the base of the IF transformer. Lot's of early Brownings have gone to the grave because of that.
Owned the 123b is a terrific rig. If you're looking for a tube rig, and don't operate above 23 don't hesitate to bid on one. They sound great (I used a +2) and receive very nicely. Thanks Mike.
This brought back memories A T-240D was the first radio I owned back in the day
Awesome video I wish I had time to make them myself but I'm so swamped I can't believe the amount of people that are sending these in to get restored. I have 2 shelves full and got 4 more in today it's crazy. Anyway you do a great job take care.
I have one of these. She is a bit tired and needs restoration. Excellent radios with character. I grew up knowing them as The School Bus.
Would you sell one of the T-240D's?
Whooops....wrong reply. Sorry!
It was so awesome to hear the receive in this classic tube radio, especially your demonstration of the tone control and squelch. Solid sounding tube fidelity from that little box. Had one available locally and didn't buy it. Now this has truly helped me make my mind up to purchase one.
I really enjoyed seeing this your valve tester I imported a similar model from the USA and installed a 230/110 step down transformer. Your tube tester are much cheaper than buying in the UK
extremely nice.. it has been cleaned.. only minor pitting.
Very nice radio. Thanks for sharing.
Same chassis as my Lafayette Comstat 25A and I have the same blown cap but mine just pushed out the insides in a complete roll, no explosion.
Thanks Mike, i learned allot watching this video. I used to own some tube type
am radios. They always sounded teriffic for listening to music.
Thanks Mike,again very great video,i learned a lot from Your video.Just love the old CB radio's.
Excellent video o tube radios. Not seen any mic plugs like that for years. i have one on my CB, it came with it fitted to a coffin mic. I did have a few as spares, but he stopped when the CB craze faded here, so I have no idea where he got them from. there is no manufactures name on them either. But like everything else, the stamped out tube for the mic pins are cheaper to make and easier and this is what they go for. Quality these day are sadly rejected for cost. Accountants run the world..... :-(
There ya go, now the light works. I see these radio's come up for sale a lot on Ebay, the 23 channel and the 40. Most of the ones I have seen were in great condition. I nearly bid on one of them, but I found out that they don't have SSB. I only own radios that have SSB as I like to do DX when skip is going on. I have a Stryker 955 HPC and a classic Galaxy 93T in mint condition, love both of these radios.
Talk skip on AM. I like that better than SSB, but that’s just me!
At 1:12:17 -- my understanding is the Foster Electrical Company of Japan created that plug in the 1970s as a copy of the larger Amphenol version, but Foster ceased manufacturing them circa 2011. Dunno where to get plugs with machined pins, but Switchcraft makes them with cable strain relief springs.
The microphone plugs bite on those also. I learned that the hard way back when I was 15 years old Trying to figure out how to wire up a mic.
Good videos wish i had time to post some but im always so busy with repairs. These are very good built radios i have also been servicing them for years and have several of the 123 and 240D still in the original unopened boxes as well as dozens of tube Messengers. Keep up the good work.
Would you sell one of the T-240D's?
I agree would you be willing to sell one of them
Great video Mike,we dont see cb kit like this much in UK,one of the main reasons 455khz filters fail ,can happen by applying DC to the filter,either a bad coupling\decoupling capacitor on the IN\OUT of filter or No caps at all!,filters can get destroys be DC applied to the 455khz Ceramic filters over time,another well known modern brand had this issue on HF rigs.
Wondering if this radio would take a Murata 455-HT filter as a upgrade?
You mention the squelch,Ive seen these effect on Vintage CB Hts of 60/70's can do similar thing with squelch.
Rob 73's
I have that same radio. I also have a colt 40 channel midnight special that looks just like it internally. I’ve got another one that’s a Shakespeare I believe that uses that same or similar chassis.
that tube been smuggled in to prision and out again you can only guess how it was smuggled
I think you'll be able to fine tune the radio , If you could loosened the IF transformer cores from top and the bottom sides separately. Nice informative video.
Nice radio MikesRadioRepair.
I just remembered I had another radio with a very similar chassis to that maybe identical I believe it was also a Robin and it had a narrow rectangular window in the front and a little tube behind it and it looked like a green bar graph that came together as you talked I can’t remember the model of it it was a 23 channel though. It was kind of similar to a magic eye tube but it was a bar graph.
Model T-123 (not T-123B)
James Bowie Thanks I’m glad you said That I couldn’t remember the model after you said it I searched it on eBay and I just bought one for 50 bucks. I’ll add that to my collection.
Nice old radio.
Mike sounds like Tom Arnold LOL
I’m glad u had some skip it’s been dead here last few days or that radio just has a really hot receiver.. thanks for the video mike
Mike is it possible to put a brighter meter light in one of those? Very nice job on this old girl.
Your video s are always great . Big fan
i have 2 of these ..i am with you with the pll boards i have 6 or so 23 channel ones they are built very well ..panasonic made most of them i think
You said once You have Messenge 1's and 2's ? My favorites!
When you say this radio is PLL synthesized, are you talking about phase locked loop? I see the switch going to the PLL board so it made me think of my J.C. Penney's phase locked loop radio that I modified with extra channels above 40 and below 1. Back in the day (mid 70's) I had the very same Hickcock tube tester when I used to repair TV's.
I wish you could go through my yellow Robyn. I’d love to use it. It sounds muffled on Receive and transmit. and it’s weak. Kind of seems like maybe it’s slightly off frequency also. On the other hand at least it looks brand new.
Man I haven't heard skip in decades. Since then we got Squidbillies that sound just like it.
Just found your channel a few weeks ago. Brings back some memories and nightmares too. How I survived the Golden Screwdriver era I don't know. So many ruined radios back in the day that people just tossed. Makes me want to cry sometimes.
I may have missed it in the video but what does the Range Expand switch do? For the life of me I am drawing a blank.
I found a radio chassis laying out in the mud and the tubes in it look just like that until I cleaned them up To see the lettering on them.
Excellent video thank you.
Good point about the longevity of vacuum tubes. in my experience unless it is a tube that is doing hard work in the circuit such as RF finals or audio output tubes in the course of it's lifetime they just rarely go bad all other things being equal. I think the myth of tubes being faulty was promulgated back in the 1950's and 60's drug store tube tester era. Possibly even by the manufacturers themselves. Those testers always read "Weak" or "Replace" The unknowing weekend TV repair guy would buy new ones only to find that the new tube didn't fix his TV. I wonder how many perfectly good 12AX7's that are fetching precious metal prices today ended up in the garbage due to these testers. I have tubes in radios here from the 1920's and 30's that are still working just fine. ATB Doug.
Great radio,had one .hope you can fix it for owner .I like metal film resistor for repacements,any chance you no where I can buy those type of 455 hrz IF cans from ,They should work on vintage a m radios right anyone .
Mike. If you would please, what brand solvent do you use to lossen the paint on the slugs of those I.F. cans?
Andy Thrasher I use Deoxit but not Deoxit Gold.Works wonders.
Mike do you possibly have a email address or phone number im looking for a good 10k ohm potentiometer wirewound 10 to 25 watt! My email is pdegroff53@gmail.com. thanks if possible!
@@1OFGODSOWN Thanks. I may be possibly playing with fire here but I used a very minute amount of acetone and ran the slug up and down a ways as soon as it loosend. worked well and didnt seem to melt the plastic tube. I have De-oxit but its the D5
@@peterdegroff1013 Your best bet would probably be Ebay for new old stock - www.ebay.com/itm/Ohmite-RES10K-Rheostat-Potentiometer-Wirewound-12-1-2W-10K-Ohm-035A-Model-E-NOS/322642564470?epid=1411853773&hash=item4b1efed576:g:i4wAAOSwAxJZ0n2N:sc:USPSPriority!33404!US!-1
That's not exactly an easy or cheap potentiometer to find.
He uses GC Electronics 10-320:
www.alliedelec.com/product/gc-electronics/10-320/70696985/
Wondering what you used for the DC block on your spectrum analyzer? I've got the same one and it's new. I'd sort of like to keep it like that. Thanks.
That is a good looking radio
looking for a colt midnight special base stand and 12 power cord with socket looks like the robyn used the same thing
You mentioned bringing a radio up slowly with a variac system, what is best item for that.
Great video! No receive light? I just heard you say you just noticed no rec light.. LMAO!!
Man I wish I had that schematic. I have an older Robin I can’t remember the model but it’s the same chassis but it’s a green 23 channel and it has the magic eye type tube as a modulation indicator. It’s like a bar graph. I need the schematic to see how the power cord wires I’m thinking it should be the same as the yellow Robin but I don’t know and I’m scared to plug it up.
Well you can clean the tube and pins it's probably been sitting in a wet box for many years, you can clean the pins with a fiberglass eraser pen or a pencil rubber the blue end or a bit of steel wool. Will isopropanol loosen the paint on the rf cans? Usually it dissolves paint very well you might find it will dissolve the paint and you should be able to turn it easily. I don't think isopropanol will melt the plastic tube I've clean plastic tubing with isopropanol and never noticed it melting, are those capacitors original I would have thought they would have had Mica capacitors probably been changed? I think using Surface Mount capacitors is better solder to a piece of wire bent in a loop as a heat dissipator. you can place them on the bottom, those film capacitors will get interference I would have thought being so close to the inductors. I would have thought the RF can next to the transformer would cause problems, it's only aluminium I would have thought they would have used still here! would be better. I don't know how you would defeat the interference from the coil being so close grounding is enough? and managed to tune it in properly. Is it an issue?? Would you get a better response having a still can here from the receiver.
Why is the jumper wire put in there then, what is the benefit in the first place of the wire mod.
You might want to try Advanced audio they might have those plugs? they make high quality studio microphones a Canadian family owned business.
Instant On. I thought that was only a vintage TV thing. It was advertised as 'Instant on' , no waiting for the warmup. Kept tubes partially warm. Remember from old TV repair in high school. Eat lots of electric as well. Yea should be labeled stand by and on then a fully off hard switch.
That would make a great 10 mtr radio
Do you still do radio repair? I could use some work on a rather special project.
Hey Mike do you have any Robyn T-240D crystals and if not do you have any Idea where I can buy any?
I have the exact same radio. Do you still do restores?
Does that use a pll02a for PLL ? I learned a lot from you by watching this! Take care! 73 de ve3hip in Welland Ontario Canada 🇨🇦
That is a fantastic transceiver. I AM curious if you swap out the final RF tube to increase the output?.
Kind regards, Eric Dee.
No, still has factory original tube in it. Increasing output in any radio is a bad idea. Radios were not designed to do "more power" and trying to do so does nothing but stress the power supply. In a tube radio that's a good way to burn up the transformer. Ask anyone who had to pay to get a power transformer replaced because they had their radio set up for "more power" if it was worth it. They will quickly tell you no.
@@mikesradiorepair ; Thank you for your time in replying. That's great advice, THANK YOU . You have a fantastic channel,GREAT content, well explained.
@@mikesradiorepair I agree. That's what they made amplifiers for.
Have a old 23channel Robyn radio into is worthfixing
Question: Why did you replace the 3 electrolytic caps with film caps? Those weren't non-polarized caps as you described. Just curious as I'm restoring a T240D myself.
If your referring to the .1uF Atlas oil capacitors they are absolutely NOT electrolytic. They are non polarized aluminum capacitors. The black line on them does NOT signify the negative end. The line on a non polarized capacitor signifies the outer foil or can.
@@mikesradiorepair That's good to know. The manuals parts list says they're electrolytic caps. C23, C24, C607. Maybe a typo on their part.
Onan Robin what is that little yellow diode by that resistor had a little burnt spot on it mine's broken half a little dial with the yellow tip on it do anybody know the volume of that
Are the yellow wires some kind of "grounded grid" hack?
Sir I have one of these
The receive was loud and went in and low bot not out thought might been dirty potentiometer but not
I can hear the skip on six but volume wide open to hear it
Any help would be greatly appreciated
When switch to pa the PA Has Plenty of volume…
And if I partially push PA I get a little more volume on radio but no where near full volume
You never explained what that "range extender" switch does. Would think it's an RF gain but it has one.
wcemichael makes the transmit much louder when turned on.
Drives the modulation a tad harder. Gives you maybe 2 or 3 watts more output.
Hi sir, I recently acquired a yellow bird and my receive is absolutely perfect however my tx is not !!! It is only pushing about a 1/4 of a watt, I have replaced the 6ba6 tubes and no go, the radio is in extremely clean condition and I would love to repair it do you have any suggestions on where to start? Possibly a capacitor or somthing is there anything common that causes this on this model ? 🤔
I would check the RF final tube first.
@@mikesradiorepair I will replace it this week and see, thanks
@@mikesradiorepair which tube is for the rf final section and is there a better replacement for the stock one ? Thanks
@@justinf6951 www.cbtricks.com/radios/robyn/t_240d/graphics/robyn_t_240d_om.pdf
Dang 'ol get down bump bump get down get down maul time AAAAAUUUUUDDIOOOOOOOOOOOOOOOOOOO bump bump I'm gone.
Cone bread! Cone bread! Cone bread!
i have two robyn t-123's i already restored one other is being restored at some point
I own two of these and one of them is MINT inside and out the other looks great and comes on but has no transmit or receive.
If it doesn't transmit or receive you may be having a problem with the solid state synthesizer circuit. Check to see if you have proper output from the synthesizer circuit at the correct frequencies.
MikesRadioRepair LOL, that is Funny since I am not a Technician but I have stayed in at least one Holiday Inn Express. 😂
I noticed the RX light isn't working, I would think it should be lit when someone talks.
What if they had no replacement resistors
Too bad users are always so hell-bent on modifying these classics. That never ends well. The first thing I do when acquiring these radios on a hamfest is bringing it back to factory-original condition. That's when they work the best. In that regard, the T-240D Yellowbirds that I have worked on/owned always had a low-cost Murata ceramic filter rigged in between the IF stages. The one in your video has the mod too, I can see it clearly (the small black plastic cube). I assume there once was a particular CB butcher who offered that "improvement" service for sale. As a result, the radio's IF passband is completely screwed up and the receiver will sound tinny. The first thing I therefore do when getting this radio is to remove that ceramic filter, restore the circuitry back to original condition and re-align the surrounding IF filters to their proper 455kHz setting. This radio from the factory has FOUR coupled IF filters (that is eight 455kHz LC tanks, 16 poles) which is more than the average vintage communication receiver which normally has 3 coupled IF filters. So there is absolutely no need for this ceramic filter. Cheers.
The ceramic 455kHz filters were factory in the later Panasonic tube type chassis. I think it was a huge improvement because it narrowed the passband. They were much less prone to adjacent channel bleed over like the earlier models.
The three T-240Ds that I found to have this ceramic filter installed were clearly "upgraded" in a later effort, not by the factory but by a third party. That could be seen by the sloppy solder work and the fact that the ferrites in the IF filters had been retuned, which cracks the white paint that the factory had applied to prevent loosening of these ferrites. And as I mentioned earlier, the receiver audio response significantly improved (for all 3 radios) after returning it all to factory state. I have never heard of, or seen this particular Japanese tube chassis being equipped with this ceramic filter on other radios from different brands (as you know this chassis was used for many other radios like Gemtronics and T-berry). So I don't know what to tell you but I doubt the factory applied these filters, sorry.
@@LifeIsTooShortForQRP I guarantee you the ceramic filter board is factory. How do I know, it's in the SAM's manual. Manufacturers sent their radios straight to SAM's. Actually the SAM's schematic shows the ceramic filter and separately shows what they call "alternate circuit" which is the earlier version. I think I have only ever seen one 240 that didn't have it. Every other 240 I have seen has the ceramic filter board.
you need a light in the receive meter
What's in your vape pen ?
I'm surprised at the amount of CB"ers still using AM there.
Just got on the radio this year and there's lots out there.
OK had a Yeasu FT-101E that blew up a cap, it looked like a pinyata being hit by a bat...lol. Paper everywhere.😣
Hey how would we be able to contact you ?
Great stuff!
I found a T123-B brand new unused in original box a few years back. Story and photos here: www.pd2h.nl/barn-find-at-the-ham-radio-flea-market/
hey Mike, can this be wired for 12v
Yes. It uses the same power socket on the back. You just need to correctly wire up a another plug for 12VDC.
there are NO non-polarized electrolytics in this radio.
Not exactly but check out these pins. www.mill-max.com/new_products/detail/55
Don't need pins, need microphone plugs that have machined pins already molded into them.
Anybody ever seen a version of these Japanese clones with RED covers? Maybe a Kris 40? I've only heard rumors but have a set of red covers that came off a radio I never saw or had-and I've had just about all of them. Looked like factory paint to me.....