I still have my TS-520S on my station desk. I purchased it new in the early 80s with money I earned on a paper route and lawn mowing (15 or 16 maybe). My decedents will have to find a home for it as it will never leave my station while I'm alive. It's never been modified and has the original tubes in it. Still puts out full output and the receives well for a radio of it's generation. Thanks for posting these light referbish videos on your TS-520. Should I ever need to work on mine, these radios are similar enough to help quite a bit.
👍Nice to see the 520 fixed up Mike. Glad you went for the yellow LEDs. I hope it gets some use on the air. With newer blackbox radios, I sometimes wonder if we have gained on one hand and, on the other, lost the ability to modify and repair our rigs. Hopefully, videos like this will encourage some newer hams to fix up some of the older rigs and get on the air with them.
Thank you for posting these videos in a straight forward style that is easy to follow. It has given me the confidence to carry out a similar refurb to a TS 520 I purchased earlier this year.
Bought my first 520 from Henry Radio in Butler Mo. in the early part of 1973. I actually went there wanting to buy the Tempo One. But they had a demo table set up with the TS520 and I went for it instead. Really loved that radio from the start. I had been using a Swan 350 up to then and the 520 was quite a step up. I traded the 520 for another rig that was not as good I found. A few years ago I bought another 520 on ebay and I have been having fun reliving my first one in the early 70s. One thing now days. 6146 finals are still easier to get than sweep tubes. Thanks for the posting. It gives me some ideas to use on mine.
Thank you so much for sharing your knowledge on the 520. I was very lucky in my purchase of a 520s from my Elmers storage, also the S/N is from 1978 the last year they made them! I bought the full cap kit and I am taking you advice on the small caps being to much work! Thanks loads. JohnBoyUtah KJ7TBR 🇺🇸😎🎙📡
Let me know if you attempt the full cap redo. Apparently many have done the full recap and deal with a broken wire matter of fact, and just replace or re-strip and solder the wire and move on.
Nice repair. The meter looks great. I have fixed a few broken meter faces by being patient enough to find a compatible meter from the same manufacturer. I like that you made an incompatible one work and it looks great!
Re doing questionable things with vinyl electrical tape, use top shelf stuff (I like Scotch 33+ or 88) and I doubt there will ever be an issue. It's the cheap stuff that goes goey that tends to bite one later, I only use that stuff for closing trash bags.
Aces, Mike! Hve FT-102, TS-530, both initial basket cases. Rebuilding was best 4 years of hobby ever spent! Problems still linger: Crystals aging, Crystal filters also...made of many crystals, plastic gears cracking, etc. Working on ZL2PD's synthesizer fix now. The projects still go on. God Bless, Sam W3IHM
I've done 4x hybrid Kenwoods 1x520 and 3x520S over the past 12 months. Replaced ALL electrolytics, All power supply resistors and All resistors and caps in the PA stages. The only issues I've had have been with worn selector switch contacts. Very enjoyable radios to rebuild in my opinion.
@@MIKROWAVE1 you just have to be careful and methodical . restore each PCB one at a time. I always replace the bulbs with LEDs and put a 100pf cap in parallel with each LED to keep the noise floor low.
Just acquired a TS-520S at a local swapfest with the matching desk mike all for 60 bucks. In pretty good shape too. He says it receives well but does not transmit. A good winter project. Just finishing a FT-101 (Mark 1) and yes, I DID replace all the electrolytics and all the cracked polys ! It looks like you used Rustoleum Winter Gray paint. I have plenty of that. If you could, please confirm that. 73 de WB4YDL Jamie
Well you get a nice result and and I think a good radio for the future or to 'Elmer-out' should the need or opportunity come up. I really appreciate anyone that restores or repairs and kindof vintage-gear. On the clamp-spacer for the electrolytics, I quit using electrical tape because with heat and time, the adhesive oozes and sometimes the tape physically displaces itself out of the clamp. Instead, I use Scotch 3M double-sided foam mounting tape--just don't peel off the backing that goes on the clamp-side. The foam tape is really good in that you can fill the area needed with very-few wraps. Additionally the 3M adhesive/foam is much-more stable in elevated temperatures. On the meter plastic, it was nice you found something that close and don't worry about the top! I have made complete new covers by using very-thin Plexiglas and bending it using a heat-gun and a wooden-mandrel. If the meter is round or has rounded corners, you have to first make the face then a formed-'band' for the sides with a second made wooden-mandrel. Sometimes the mechanical adjustment is a little tricky to reinstill, in-that you sometimes have to fashion a collar to hold the salvaged screw-assembly (if it will not flush-mount to the face) from the old meter; otherwise you can just pre-adjust it and not make a hole at all. I actually try to cut the whole adjustment assembly out completely for reuse. If your handmade cover comprises several pieces, use the actual Plexiglas-solvent and a syringe, rather that say super-glue; as super-glue tends to run and also the fumes will fog the plastic--short of that, just use very small amounts of epoxy. In regards to using LEDs, most of the high-brightness ones have a water-clear lens. This will usually cast lines or unwanted points of light (hot-spots). To remedy this, you can use some green Scotch Brite to roughen to clear surface, and it will greatly diffuse the light. If you are still plagued by lines and/or hot-spots, you can cut pieces of milky-white plastic (usually found in food storage containers) adding as many layers as it takes to give a nice defused-appearance. Another trich is to daub a bit of rubber-cement or silicone on the LED. I've done this many times (mostly on stereo equipment) and also find that you can also series the LEDs to cut down on the dissipation of the dropping resistor(s). On the Kenwood phenolic-PCBs, you are right, they are both fragile (sometimes putting a fracture clear across the board, even when only gently-flexed!) and heat-sensitive whereby the adhesive holding the traces crystalizes. If you have to get to the back side, I only remove enough wires to allow the PCB to pivot. If you do lift a trace, many times it is just better to run a piece of tinned bus-wire in its place. However, many times I did exactly what you did to avoid damage. In servicing hundreds of stereos, these PCBs and rats-nest wiring were in a pretty much all of them back in the day. 73...
Double Wow. I bow to the voice of experience. Many of us are spoiled on good PCB materials and never have to deal with the commercial grade stuff for entertainment systems.
@@MIKROWAVE1 Worked in a low-end warranty center: Emerson, Capehart, JC Penny, Airline, Silvertone, Panasonic, Delmonico, MaggotBox, Lloyds , Ge, RCA, Soundesign, Tempo, Allegro; The scars run deep! Later worked in a high-end warranty center: SAE, MacIntosh, B&O, TEAC, Revox, Ampex, Altec, JBL, Pioneer, Dual, Harmon-Kardon, Nakamichi; Sansui, Kenwood, Carver, NAD; There is a God!
Motivation to restore Ten-Tec Triton II. Got it at Hamfest two years ago with accessories for $75. Put new Dial String in and tested it some and its works although every control is oxidized, purchased DeOxit and just need "motivation" (Kick in the Butt) to finish cleanup ; ) Thank You.
Great Video Mike! The dial cover turned out great. The way you mounted the VFO upside down reminded me of one time my VFO (early 80’s) would stop oscillating. I would pull it apart and it would start back. Put it back together, after a few weeks, it would quit again. So I mounted it upside down with the cover off until it quit again. Turned out to be a FET in the VfO thAt would quit working randomly ( no heat or cooling issue). Like to have never found it. Happy to say, Im still using mine today. I recapped mine on my channel. Thanks for sharing your experience! Take Care-Larry W4PJP
In my opinion That not just any old rig That a 520 kenwood That a example of a machine from when the Japanese were making bones And it a Kenwood One of my very favorite machines a great time in the history of amateur HF The likes of which we not likely to see again My 520s are collecting dust
They looked at the best of the 50-60s US designs and when you study the schematics - they are excellent non-Japanese designs right out of the Handbook. All standard and straightforward and unlike the odd biased and crazy designs of many early Japanese commercial equipment. And they used COTS parts. And heavy chassis and transformers. Add the excellent features like onboard power and slick layout and low production costs, and the rest is history.
Thanks for watching. I have a theory on radios that you buy off Ebay or obtain at a Ham Flea market. I only buy broken radios. That way I am never disappointed!
Yes, I did enjoy that video, in some ways it's a nicer rig than my ts530, although it doesn't have digital readout and doesn't seem to have topband and the warc bands
Hi, I really like this part 2 and part 1 which I enjoyed. I hope someday I will be able to fix my own TS520 which the only fault is the power tube and the choke plus caps. My wife and me enjoyed this radio since 1980. Please enjoy the pics that I am going to send you....VA7VB
Beautiful radio, and excellent work, Mike. Thank you! That sweet old rig has a better 'sound' on Rx than my Yaesu FTdx3000. Which is why I'm forever in love with my Heathkit SB-101. It also has better sounding audio than ANY modern digital DSP based rig. New rigs are just plain tiring to listen to, and I don't know why. Be well from the old buzzards and smart young makers and hackers in Michigan :)
You've done a remarkable job here! What I would love to see is a visual on how to align these things. No one has posted a video on a full alignment. People have aligned these things by ear for decades so it can't be that hard. In my case, the PLATE knob is pointing straight down on 40 meters and away from 7mhz position. Full power out, IP in range, but how does one fix this issue? Why does this happen in the first place? Your help is much appreciated.
@@MIKROWAVE1 Mike If it's that simple I'll buy you a bottle of wine! It's a Kenwood 820S, the knob has a metal triangular pointer, which is pointing straight down away from the markings. Would loosening the setscrew move that metal triangle also? It almost looks like it's 2 separate peices
Nice video Mike. I love the chains on the ganged variable cap -- much better than the O-rings on the HW-101. That superglue on the screwdriver is a really useful idea. But what do you mean about "a concoction of superglue and baking soda"? Thanks for the tip on the LEDs. I'm getting tired of replacing the incandescents in my boatanchors. Looks like softwhite LED is the way to go. 73 Bill N2CQR
Check out some videos on this baking soda idea. It basically mixes with the thick formula superglue to form a paste that hardens like plastic which is very useful for bonding and filling.
Mike, Great videos that I followed to fix an old 520 that I picked up from a SK. While trying to bring up the voltage at 40 volts, I measured only 20 volts at the fuse and power switch. Is this a normal reading when ramping up the voltage?
Great video and it is a hard job. I noticed you replaced the finals 6146 tubes did you use 6146B and did you neutralize the tubes? I would guess you did, I hope you make a video on that replacing finals and neutralizing the finals. Voltage on the Neutralizing cap. Also are you using JIS Japanese industrial Standard screw drivers or regular Philip type screw driver? thanks Mike
Ha! I have no idea what a JIS is. And I'm really not a 6146 sensitive guy. I have never met one 6146 variant that you can not neutralize, if you are willing to adjust the cap values to accommodate the slight differences. The tubes I put in are supposed to be similar to 6146A's. The neutralization is good - no fribblies on any band. I will go through the neutralization process on the rig in another video with a few types of 6146's. Might be interesting.
@@MIKROWAVE1JIS is Japanese Industrial Standards, they use a slightly different Phillips standard than the rest of the world, less taper in the slots so it isn't as prone to cam out, and inadvertantly extra prone to cam out if used with a Phillips driver that will never seat properly. The proper "JIS" drivers really do grab them better. Common misunderstanding with old Japanese motorcycles, the screws were soft, but they were good enough if you had the right tools.
@@MIKROWAVE1 If you don't have the JIS screwdriver bit, you can "JS" it with a bit of super glue in the head of the screw if the screw is almost rounded out. Which is I think what you did on a previous video. I didn't know this even though I was a mechanic on trucks for 27 years until I watched W2AEW do a video on it.
At the time, the dual gate mosfet was the logical replacement that came close to pentode tube signal performance and accepted AGC nicely and they had a low noise figure - so quiet too.
Hi there, I almost hate to make the comments more than 73... but i will. I just received one of these radios as a wedding gift and I am ecstatic. Everything seems to work well except for the meter and VFO lamps. I am wondering if you could tell me which LEDs you used in this resto. I would like to order the same "amber" ones you used.
I ordered this Kit. www.amazon.com/EDGELEC-LED-Emitting-Assorted-Diffused/dp/B07PVVL2S6/ref=sr_1_5?crid=2T1K016CEZZX&keywords=LED%2Bkit&qid=1686831381&sprefix=led%2Bkit%2Caps%2C114&sr=8-5&th=1
The Operator Manual and Service Manual are both readily available on this popular radio. I would start with the BAMA site but there are many groups with free PDF copies out there.
@@MIKROWAVE1 Hmm, the LEDs you used don't require a current limiting resistor of any sort? I understand what you did to decrease the brightness by adding resistance which I thought was in addition to the normal current limiting resistor. Thought a normal LED would go boom without current limiting of some sort?
@@MIKROWAVE1 You are damn lucky this thing still worked. Imagine a doctor removing and reinserting organs as transplants because they might someday fail.
Basically critical large signal intercept numbers are important only if you are contesting or operating field day with a big signal next door! Filtering in the front end is more important for radios with low intercept points. Todays SDRs are particularly vulnerable. The TS-520s Mosfet based design and front end preselector filtering was plenty good enough for typical receivers of the day. Same goes for the Yaesu FT-101.
I still have my TS-520S on my station desk. I purchased it new in the early 80s with money I earned on a paper route and lawn mowing (15 or 16 maybe). My decedents will have to find a home for it as it will never leave my station while I'm alive. It's never been modified and has the original tubes in it. Still puts out full output and the receives well for a radio of it's generation. Thanks for posting these light referbish videos on your TS-520. Should I ever need to work on mine, these radios are similar enough to help quite a bit.
👍Nice to see the 520 fixed up Mike. Glad you went for the yellow LEDs. I hope it gets some use on the air. With newer blackbox radios, I sometimes wonder if we have gained on one hand and, on the other, lost the ability to modify and repair our rigs. Hopefully, videos like this will encourage some newer hams to fix up some of the older rigs and get on the air with them.
These old sets are a great way to start out for low $ while learning.
Thank you for posting these videos in a straight forward style that is easy to follow. It has given me the confidence to carry out a similar refurb to a TS 520 I purchased earlier this year.
Thanks for watching and have fun. and watch out for high voltage!
Bought my first 520 from Henry Radio in Butler Mo. in the early part of 1973. I actually went there wanting to buy the Tempo One. But they had a demo table set up with the TS520 and I went for it instead. Really loved that radio from the start. I had been using a Swan 350 up to then and the 520 was quite a step up. I traded the 520 for another rig that was not as good I found. A few years ago I bought another 520 on ebay and I have been having fun reliving my first one in the early 70s. One thing now days. 6146 finals are still easier to get than sweep tubes. Thanks for the posting. It gives me some ideas to use on mine.
Those radios were a lot of fun and the 6146s are tough bottles!
Excellent video Mike! Just picked up a 820s that needs some tlc and found your video very helpful!
Thank you so much for sharing your knowledge on the 520. I was very lucky in my purchase of a 520s from my Elmers storage, also the S/N is from 1978 the last year they made them! I bought the full cap kit and I am taking you advice on the small caps being to much work! Thanks loads. JohnBoyUtah KJ7TBR 🇺🇸😎🎙📡
Let me know if you attempt the full cap redo. Apparently many have done the full recap and deal with a broken wire matter of fact, and just replace or re-strip and solder the wire and move on.
Nice repair. The meter looks great.
I have fixed a few broken meter faces by being patient enough to find a compatible meter from the same manufacturer. I like that you made an incompatible one work and it looks great!
Occasionally people do part out these radios, but better to save the radio and find a similar replacement meter!
@@MIKROWAVE1 I have found meters from the same OEM that were in a different device and had completely different markings, but have had usable parts.
Re doing questionable things with vinyl electrical tape, use top shelf stuff (I like Scotch 33+ or 88) and I doubt there will ever be an issue. It's the cheap stuff that goes goey that tends to bite one later, I only use that stuff for closing trash bags.
You can get cap kits with the proper clamps so you don't have to do this trick!
Aces, Mike! Hve FT-102, TS-530, both initial basket cases. Rebuilding was best 4 years of hobby ever spent! Problems still linger: Crystals aging, Crystal filters also...made of many crystals, plastic gears cracking, etc. Working on ZL2PD's synthesizer fix now. The projects still go on. God Bless,
Sam
W3IHM
Yes this is a real issue. I did a Drake TR3 that had aged crystals. You have to tune everything off recommended frequencies to get it re-aligned.
I've done 4x hybrid Kenwoods 1x520 and 3x520S over the past 12 months. Replaced ALL electrolytics, All power supply resistors and All resistors and caps in the PA stages.
The only issues I've had have been with worn selector switch contacts. Very enjoyable radios to rebuild in my opinion.
Wow! How did you make out with the wiring? I mean did the wires hold up to being removed and replaced?
@@MIKROWAVE1 you just have to be careful and methodical . restore each PCB one at a time. I always replace the bulbs with LEDs and put a 100pf cap in parallel with each LED to keep the noise floor low.
Good job Mike
Thanks for watching.
Cool.
I'm gonna do mine one of these days.
Hey I just met the radio and I like the way it is built.
Just acquired a TS-520S at a local swapfest with the matching desk mike all for 60 bucks. In pretty good shape too. He says it receives well but does not transmit. A good winter project. Just finishing a FT-101 (Mark 1) and yes, I DID replace all the electrolytics and all the cracked polys ! It looks like you used Rustoleum Winter Gray paint. I have plenty of that. If you could, please confirm that. 73 de WB4YDL Jamie
Excellent winter project! Be careful of the HV!
Well you get a nice result and and I think a good radio for the future or to 'Elmer-out' should the need or opportunity come up. I really appreciate anyone that restores or repairs and kindof vintage-gear.
On the clamp-spacer for the electrolytics, I quit using electrical tape because with heat and time, the adhesive oozes and sometimes the tape physically displaces itself out of the clamp. Instead, I use Scotch 3M double-sided foam mounting tape--just don't peel off the backing that goes on the clamp-side. The foam tape is really good in that you can fill the area needed with very-few wraps. Additionally the 3M adhesive/foam is much-more stable in elevated temperatures.
On the meter plastic, it was nice you found something that close and don't worry about the top! I have made complete new covers by using very-thin Plexiglas and bending it using a heat-gun and a wooden-mandrel. If the meter is round or has rounded corners, you have to first make the face then a formed-'band' for the sides with a second made wooden-mandrel. Sometimes the mechanical adjustment is a little tricky to reinstill, in-that you sometimes have to fashion a collar to hold the salvaged screw-assembly (if it will not flush-mount to the face) from the old meter; otherwise you can just pre-adjust it and not make a hole at all. I actually try to cut the whole adjustment assembly out completely for reuse. If your handmade cover comprises several pieces, use the actual Plexiglas-solvent and a syringe, rather that say super-glue; as super-glue tends to run and also the fumes will fog the plastic--short of that, just use very small amounts of epoxy.
In regards to using LEDs, most of the high-brightness ones have a water-clear lens. This will usually cast lines or unwanted points of light (hot-spots). To remedy this, you can use some green Scotch Brite to roughen to clear surface, and it will greatly diffuse the light. If you are still plagued by lines and/or hot-spots, you can cut pieces of milky-white plastic (usually found in food storage containers) adding as many layers as it takes to give a nice defused-appearance. Another trich is to daub a bit of rubber-cement or silicone on the LED. I've done this many times (mostly on stereo equipment) and also find that you can also series the LEDs to cut down on the dissipation of the dropping resistor(s).
On the Kenwood phenolic-PCBs, you are right, they are both fragile (sometimes putting a fracture clear across the board, even when only gently-flexed!) and heat-sensitive whereby the adhesive holding the traces crystalizes. If you have to get to the back side, I only remove enough wires to allow the PCB to pivot. If you do lift a trace, many times it is just better to run a piece of tinned bus-wire in its place. However, many times I did exactly what you did to avoid damage. In servicing hundreds of stereos, these PCBs and rats-nest wiring were in a pretty much all of them back in the day.
73...
Double Wow. I bow to the voice of experience. Many of us are spoiled on good PCB materials and never have to deal with the commercial grade stuff for entertainment systems.
@@MIKROWAVE1 Worked in a low-end warranty center: Emerson, Capehart, JC Penny, Airline, Silvertone, Panasonic, Delmonico, MaggotBox, Lloyds , Ge, RCA, Soundesign, Tempo, Allegro; The scars run deep!
Later worked in a high-end warranty center: SAE, MacIntosh, B&O, TEAC, Revox, Ampex, Altec, JBL, Pioneer, Dual, Harmon-Kardon, Nakamichi; Sansui, Kenwood, Carver, NAD; There is a God!
Motivation to restore Ten-Tec Triton II. Got it at Hamfest two years ago with accessories for $75. Put new Dial String in and tested it some and its works although every control is oxidized, purchased DeOxit and just need "motivation" (Kick in the Butt) to finish cleanup ; ) Thank You.
Good luck on restoring that classic!
Great Video Mike! The dial cover turned out great. The way you mounted the VFO upside down reminded me of one time my VFO (early 80’s) would stop oscillating. I would pull it apart and it would start back. Put it back together, after a few weeks, it would quit again. So I mounted it upside down with the cover off until it quit again. Turned out to be a FET in the VfO thAt would quit working randomly ( no heat or cooling issue). Like to have never found it. Happy to say, Im still using mine today. I recapped mine on my channel. Thanks for sharing your experience! Take Care-Larry W4PJP
A lot of real repair guys watched this video and I am in amazement.
Wow, the 10m band is much less noisy on this rig than my FTDX-10!
Something to be said for a real dual gate mosfet front end and lots of tuned circuits in a receiver.
In my opinion
That not just any old rig
That a 520 kenwood
That a example of a machine from when the Japanese were making bones
And it a Kenwood
One of my very favorite machines a great time in the history of amateur HF
The likes of which we not likely to see again
My 520s are collecting dust
They looked at the best of the 50-60s US designs and when you study the schematics - they are excellent non-Japanese designs right out of the Handbook. All standard and straightforward and unlike the odd biased and crazy designs of many early Japanese commercial equipment. And they used COTS parts. And heavy chassis and transformers. Add the excellent features like onboard power and slick layout and low production costs, and the rest is history.
@@MIKROWAVE1 Yes and a really good neat quailty layout
Not any skimping or crazyiness I can see
As always
TNX FOR A GREAT VIDEO
That was great, thanks 👍🏻🇬🇧
Thanks for watching. I have a theory on radios that you buy off Ebay or obtain at a Ham Flea market. I only buy broken radios. That way I am never disappointed!
Yes, I did enjoy that video, in some ways it's a nicer rig than my ts530, although it doesn't have digital readout and doesn't seem to have topband and the warc bands
The evolution and worldwide marketing of the hybrids in the 70's, with both Kenwood and Yaesu, produced many variants on the basic solid designs.
Hi, I really like this part 2 and part 1 which I enjoyed. I hope someday I will be able to fix my own TS520 which the only fault is the power tube and the choke plus caps. My wife and me enjoyed this radio since 1980. Please enjoy the pics that I am going to send you....VA7VB
The event of shorting the tune cap can take out the plate choke pronto. Its not too bad in there and easy to work on. They used good parts.
Beautiful radio, and excellent work, Mike. Thank you! That sweet old rig has a better 'sound' on Rx than my Yaesu FTdx3000. Which is why I'm forever in love with my Heathkit SB-101. It also has better sounding audio than ANY modern digital DSP based rig. New rigs are just plain tiring to listen to, and I don't know why. Be well from the old buzzards and smart young makers and hackers in Michigan :)
And that is with old caps and a tiny speaker onboard!
Nice to see you again Mike. I have a TS530SP, had to rebuild the front end. CW is a little weird as it has a 500Hz offset. Great rig though.
I have not checked it on CW. Sound like I need a little follow up video on CW operation.
amazing !
Thanks for watching!
You've done a remarkable job here! What I would love to see is a visual on how to align these things. No one has posted a video on a full alignment. People have aligned these things by ear for decades so it can't be that hard. In my case, the PLATE knob is pointing straight down on 40 meters and away from 7mhz position. Full power out, IP in range, but how does one fix this issue? Why does this happen in the first place? Your help is much appreciated.
Try turning the dial fully clockwise.then loosen the setscrew and put the pointer just above 28.
@@MIKROWAVE1 Mike If it's that simple I'll buy you a bottle of wine! It's a Kenwood 820S, the knob has a metal triangular pointer, which is pointing straight down away from the markings. Would loosening the setscrew move that metal triangle also? It almost looks like it's 2 separate peices
Wow, Someone else knows you can rebuild/repair plastic parts by using baking soda and super glue !
Nice video Mike. I love the chains on the ganged variable cap -- much better than the O-rings on the HW-101. That superglue on the screwdriver is a really useful idea. But what do you mean about "a concoction of superglue and baking soda"? Thanks for the tip on the LEDs. I'm getting tired of replacing the incandescents in my boatanchors. Looks like softwhite LED is the way to go. 73 Bill N2CQR
Check out some videos on this baking soda idea. It basically mixes with the thick formula superglue to form a paste that hardens like plastic which is very useful for bonding and filling.
@@MIKROWAVE1 It's an ancient middle eastern secret. Produces NASTY fumes though!
Mike, Great videos that I followed to fix an old 520 that I picked up from a SK. While trying to bring up the voltage at 40 volts, I measured only 20 volts at the fuse and power switch. Is this a normal reading when ramping up the voltage?
Can you provide a part number and source for the light replacements? I have a Kenwood TS-790 that I am working on refurbishing.
What about printing out a new front for the meter from SUNLU Crystal Clear Filament.
My kid is a 3D guy. I will ask him about this stuff.
Great video and it is a hard job. I noticed you replaced the finals 6146 tubes did you use 6146B and did you neutralize the tubes? I would guess you did, I hope you make a video on that replacing finals and neutralizing the finals. Voltage on the Neutralizing cap. Also are you using JIS Japanese industrial Standard screw drivers or regular Philip type screw driver?
thanks Mike
Ha! I have no idea what a JIS is. And I'm really not a 6146 sensitive guy. I have never met one 6146 variant that you can not neutralize, if you are willing to adjust the cap values to accommodate the slight differences. The tubes I put in are supposed to be similar to 6146A's. The neutralization is good - no fribblies on any band. I will go through the neutralization process on the rig in another video with a few types of 6146's. Might be interesting.
@@MIKROWAVE1JIS is Japanese Industrial Standards, they use a slightly different Phillips standard than the rest of the world, less taper in the slots so it isn't as prone to cam out, and inadvertantly extra prone to cam out if used with a Phillips driver that will never seat properly. The proper "JIS" drivers really do grab them better. Common misunderstanding with old Japanese motorcycles, the screws were soft, but they were good enough if you had the right tools.
@@MIKROWAVE1 If you don't have the JIS screwdriver bit, you can "JS" it with a bit of super glue in the head of the screw if the screw is almost rounded out. Which is I think what you did on a previous video. I didn't know this even though I was a mechanic on trucks for 27 years until I watched W2AEW do a video on it.
59 59 again again 59 59 again again
I once gave in a contest 5 7 report the contester came to me and said it should be 5 9.🤣🤣🤣
Good luck in the contest. Ha. That's what I get. I actually have had two bosses at companies that were rabid contest men.
In the comments and elsewhere you mentioned that "two gates FET" is good for the front end design. In one line or two, could you say why please?
At the time, the dual gate mosfet was the logical replacement that came close to pentode tube signal performance and accepted AGC nicely and they had a low noise figure - so quiet too.
That's right. I often see a preamplifier with a 2-gate FET at the input and the second gate is held at a fixed potential for no apparent reason.
Hi there, I almost hate to make the comments more than 73... but i will. I just received one of these radios as a wedding gift and I am ecstatic. Everything seems to work well except for the meter and VFO lamps. I am wondering if you could tell me which LEDs you used in this resto. I would like to order the same "amber" ones you used.
I ordered this Kit. www.amazon.com/EDGELEC-LED-Emitting-Assorted-Diffused/dp/B07PVVL2S6/ref=sr_1_5?crid=2T1K016CEZZX&keywords=LED%2Bkit&qid=1686831381&sprefix=led%2Bkit%2Caps%2C114&sr=8-5&th=1
Do you have any "go-to" websites to get service manuals from, for these older radios?
Enjoyed the video.
Thanks for posting.
The Operator Manual and Service Manual are both readily available on this popular radio. I would start with the BAMA site but there are many groups with free PDF copies out there.
Great work Mike...did the LEDs already have current limiting resistors included? 73 - Dino KLØS
There is a spare contact on top of the terminal strip, so you can easily mount a resistor. I did not do it. Seems fine.
@@MIKROWAVE1 Hmm, the LEDs you used don't require a current limiting resistor of any sort? I understand what you did to decrease the brightness by adding resistance which I thought was in addition to the normal current limiting resistor. Thought a normal LED would go boom without current limiting of some sort?
Where js the panadapter? You gave him a 59 but he was only 551/2. Who replaces parts that work in a working transceiver. You are asking for trouble.
I got one of those panadapters that had about 35 tubes at the antique radio show a few years ago.
@@MIKROWAVE1 You are damn lucky this thing still worked. Imagine a doctor removing and reinserting organs as transplants because they might someday fail.
Ts 520 IP - 45 dbm !!!
Basically critical large signal intercept numbers are important only if you are contesting or operating field day with a big signal next door! Filtering in the front end is more important for radios with low intercept points. Todays SDRs are particularly vulnerable. The TS-520s Mosfet based design and front end preselector filtering was plenty good enough for typical receivers of the day. Same goes for the Yaesu FT-101.
@@MIKROWAVE1 Yes. Vy 73! Poland