I built one of those Radio Shack regen receivers when I started SWLing. Saved up and finally got a Star Roamer. It was magic for a few weeks until I found the ham bands and realized I needed a BFO. I had a great time building those, amazing to me that I got them working with how little I knew. Thanks for bringing back some great memories.
Excellent, Mike! I'm glad I caught this series. Very similar to my Kenwood TS-830S. I am psyching myself up to do an alignment and put it on the air after not doing anything with it for 5 years while I pursued other interests. Probably won't need much work other than replacing the caps as it is in almost pristine condition. I would really like to see you do an alignment on an 830S as I don't want to do it "alone", given all the high voltages present. Your help and knowledge would be greatly appreciated!
Stunning series! Oh man, thank you SO much Mike. Ya know, you're not the first. In dimly light 'back corners' of every Motorola research lab and field radio repair facility sits what? Nothing by HP, Agilent, Tektronix, nor Rhose & Schwarz. It is a Star Roamer! I've seen this! In labs! Motorola ones! Mike, your videos are the golden standard by which every other 'radio guy' video is judged. They all fail. Thank you Sir :)
Just fantastic. I love seeing the radio in actual use on the air. This was a wealth of information here. And for years your videos have had magnificent quality and lighting!
Thanks for watching my videos. Hey I really take only basic steps on lighting! I I can't see it, I assume the camera can not either! By the way the tripod went over onto the floor hard this week, and my camera is dead dead dead. So a new one is on the way that hopefully will work.
@@MIKROWAVE1 I'm truly sorry to hear that. Careful with a new camera! Sometimes, depending on the manufacturer, the tint is a little blue thereby ruining all the warmth your videos have. It sounds silly but in a way you've created a brand that is very welcoming and a blueish tint could destroy that with lab like coldness. Buy your camera the same model or buy wisely hihi ... sounds severe huh? It isn't. We just love your videos. Keep that quality and warmth! thanks again for all you do. These 520 videos are GOLD as these radios once again see a resurgence in popularity
👍Thanks Mike. Fantastic explanation of neutralisation and neutralization plus some top tips. I wish that I had been able to watch this years ago before attempting the process on my old FT-101.
I like the forward method that they use and the clever screen grid switch in the rear. This makes it easy if you do not get a shock or short something in the cage!
@@MIKROWAVE1 Yes, the switch is a good idea. My early FT-101 had 6SJ6C finals, no switch and the procedure was basically to adjust the neutralisation for smooth/equal plate current rise either side of the dip point. I assume this was an indication that no spurious oscillations were occurring whereas a sharp rise on one side of the dip indicated some unwanted response was present.
My first radio was a used TS-520 I bought in 1996. I checked the neutralization using a borrowed RF volt meter on the advice of an experienced ham. I was terrified of those bare plate leads but I got the job done. Whew! I traded the 520 for a TS-430 just to get away from HV. What a mistake. I just bought a pristine 520 because I missed it. The 520 is a radio with character and a pleasure to use. More and more people realize that now and clean 520s are getting scarcer and more expensive.
That is quite a story on the old 520! That screen grid switch on the back is clever. This allows the unit to be at low enough power for both neutralization and for driving transverters like 6 or 2M or even WARC Band or 160M converters.
I'm enjoying your TS-520 videos. I have a TS-520 I bought from AES in 1975. It was my main rig until 1997, though not used heavily. I still have it, it has never been touched and still works fine. But I know I'm pushing my luck, and probably will replace the large electrolytics one day, and videos like these are nice to refer to. Thanks, K2AS
Just amazing how these things keep on ticking when decently treated over the years! There will come a point when the caps all start to fail across the product. I saw this suddenly happen with the ARC-5 receivers in the 90s.
Thanks, so much for this series! I have two TS-520s that I have recapped, lubed and serviced the VFOs. One rig needs the 6146as replaced and neutralized. Believe it or not, I have no scope but do have a VTVM. Was hoping you would show the procedure with that! 😒. When using the receiver method, are you looking for a dip in the SWR meter? DE K1TB
Very good job in explaining the neutralization well done and one of the best I've seen. Glad you took the time and are kind enought to do so. Enjoyed watch your videos 73s Mike wb7qxxu
Aces, Mike! The worst HV cage on these era rigs is the one in the FT-102 with THREE 6146's crammed in there! The load cap hit the plate wire on mine, until I figured out it wasn't the band switch. Eeeek! 73's W3IHM ....oh, hrd 10 m JA, ZL, etc, too, on my dual half-wave 10 m vertical. (....think Ringo Ranger, but on 10...)
Yes yes yes - the panadaptor and waterfall are techniques that once were very special and expensive , reserved only for government work! But have arrived thanks to cheap PCs and software, and at low cost. Displays were already in use by WW2 which could monitor a span of several MHz.
I had an FT101-ZD which had a defective DG-MOSFET once. The symptoms were pretty funny. You could use it fine on receive and also transmit on it, but the moment you hit ~30W just once, even with a modulation peak, the radio was completely dead. Both on RX and TX, and only power cycling made it work again. It was the first transistor in the "RF UNIT", so it likely got hit by some static from the antenna and was slightly damaged. In a way that it became a thyristor, which triggered as soon there was enough RF drive on the gate in transmit mode.
You only find out if they are good when you remove them! 10M with the old 8298 pulls is not bad. Just over 100W. It does 120W on 80M. But I lower the ip to 200 mA on CW and that brings it down a bit.
You certainly managed to buy a rig that is great repair practice! I shudder to think of someone with less knowledge and experience buying it hoping to repair it. BTW, I have worked the world on 10 meters from CO in my car with a 9 ft whip antenna, running a modified SSB CB tuned up to 18 W PEP on 10 meters. Australian contacts were so common for months that I could recognize a few of them by the sound of their voice.
The last three cycles were worse and worse in turn. The one in the 90s was not bad. But this one is showing signs of greatness already. Yes I remember - I built a 15M transverter for a CB that I ran in the truck back in college. It was made from CB parts!
I have a QUESTION I would like you to give your rating on the rig ? I hold these in very high regard I have a brand new in the box 520 kenwood I do not mean I still have the box I mean I have one that is still factory sealed I removed it from its factory wrappings I put in on the air one time and put it back in the box I bought it from a fella who was gifted it He was going to get his ticket and his parents bought him a rig He never did get his ticket and the rig just sat in his closet unopened Anyway I have great memories that involve the use of 520 kenwood`s I no longer operate anything other than QRP cw and likely will never use my old rigs again Your thoughts on exactly where a 520 fits in the scheme of things would be appreciated I think they are great :)
Being totally ignorant on these Hybrids, because I like the older separates and have more experience there, boy am I glad I picked the 520 as my first candidate. Its just about a perfect beginners radio.
Also; YOU were not reading the TS-520 dial correctly. You read off the LSB or USB markers, depending on which mode you are in. And to adjust the dial readout using the calibrator, assuming it's tracking correctly, the dial is on a slip clutch so you can just move it while holding the knob.
Yes, much prayer is needed. I know I have done this in my Drake TR4s radios. I not done so in my TS520. or other tube rigs. I would have used either my RF voltmeter or a my Scope. Scope most likely.
The early mosfets were essentially unprotected and the fear factor was real. They did add diodes internally. Now they are quite well under control and protected. Best way to fight static is to only do work in high humidity!
You say nobody knows what an RF VTVM is any more. I don't know about that, lots of HP 410Bs out there with the tube AC probe. They're just too useful to get rid of.
@@MIKROWAVE1 yep, That's the alternate method in the service bulletins. The other way is to match the power peak out to the current dip while fiddling the trimmer cap. I'm just wondering why the HV needs disconnected since killing the screen voltage shuts the tubes down
