In above my head

[78turbo]

I have one of the AR3500's that is in need of some serious help. At times there is no modulation on any setting (LSB, USB, FM, AM) and a squeal if powered to more than 25W. Other times there is great modulation with it set to full output an any setting. I have no issue with digging into things and fixing problems, but I just don't think I have the knowledge and tools to tackle a radio like this.

I am interested to know if there is anyone or any place that can do a complete service/alignment on these rigs.

I had one years ago that had some issues and sent it off to Bob's after talking to a person on the phone. I never saw that radio again and nobody there knew anything about it, even though tracking showed it delivered. I don't want to go through that again.

 

[nomadradio]

Kinda like getting a 1966 MG-B straightened out to be a daily driver again. Parts you can't get and not many folks with hands-on repair experience.

That radio was produced only in small quantities. Small compared to the mainstream radios sold today. This had an effect on build quality. That's a statistical kind of thing. The more of an item you make, the lower the percentage of duds. I would start with the mounting screws around the edge of the main circuit board. They come loose and cause intermittent foolishness.

It's probably about 35 years old. This is an awkward age. It's full of aluminum electrolytic capacitors. They have a 'use-by-date' kind of character. Age alone makes them deteriorate. Mileage speeds up the aging process. It has dozens of them in there. Common practice is called "re-capping". As in replacing each and every one of three to four dozen of them.

The bonus is that only then will you know if the radio has additional problems. Failed electrolytic caps produce any number of wacky performance symptoms. And they can become intermittent.

The older the radio, the bigger the leap of faith replacing all those caps. No other way to find out if your troubles will all be solved that way, or none of them.

One thing that can be done is to use a ESR meter. Equivalent Series Resistance is a measurement that can usually be done in-circuit without unsoldering anything., This could identify individual faults, and allow you to replace only the parts that have failed so far. But only if you have a reliable ESR meter. We have come to call this process "electronic whack-a-mole". Once the first few caps go bad, the rest of them will be a slow-motion string of dominoes, following behind one by one.

Our shop stopped supporting the 3300/3500 radios some time ago, and we sold off our parts radios. Once the failure-prone stuff had been robbed from all the junk chassis we had to admit it was time to move on.

Make no mistake, this radio was popular for a reason. When it was good, it was good. So was the 1966 MG-B.

73

 

[BC Coyote]

AR3500. Run away don't just walk. They were a cutting edge radio when new, but they are nothing but trouble at 30+ years old. They are notorious for drifting wildly on SSB when they get old.

Save yourself a lot of time, money and hassle and buy a 5555Nii. Does everything the 3500 does and so much more, brand new, for a couple bills.

 

[78turbo]

Kinda like getting a 1966 MG-B straightened out to be a daily driver again. Parts you can't get and not many folks with hands-on repair experience.


73

Thanks for the lengthy response to this inquiry. I have re-capped a radio or two recently and had good results with it. I did not even think to check the board mounting screws, thanks.
I know that these are considered somewhat fragile to repair due to the odd parts used. Oddly enough, the first one I sent in was fully loaded with all options and was purchased new in the box back in the late 80's. Way ahead of their time back then, and not cheap either.

On a separate note, I did help a friend go completely through and rebuild a 1968 Triumph GT6 from the frame up. She drove it daily for several years.

 

[DelR]

AR3500. Run away don't just walk. They were a cutting edge radio when new, but they are nothing but trouble at 30+ years old. They are notorious for drifting wildly on SSB when they get old.

Save yourself a lot of time, money and hassle and buy a 5555Nii. Does everything the 3500 does and so much more, brand new, for a couple bills.

I see that 5555Nii at Amazon for 259.00. I am writing my letter to Santa, now.