Sony ICB-2010

[TM86]

Finally decided to open up one of the few AM only radios I own. Another "Why did I bid on that?" eBay purchase. Sony ICB-2010.


Don't know why the previous owner stopped using it. May have been the power cord.


Or possibly the microphone connector.


Opened it up to see how much damage there was. Surprisingly, I don't see anything other than where the Sonybond has corroded a few bare metal jumpers.

Here's another look with the speaker out of the way.

And here's a close up of the PLL section with the cover off.


Yes, that's a uPD861C in there. I only see two crystals in the radio, so it's probably set up for ROM mode.

Sadly, Klondike Mike does not currently a carry a kit for this unit, so I'm going to have to catalog and order the caps myself. Only 15 or so, so not really a big pain, just a medium sized one.

BTW, I have zero service info for this radio, so if anyone has any to pass along it would be very helpful.

If I don't post on this again you'll know things didn't go well.

 

[TM86]

Got lucky, have all the caps I need in my stash.

But I've already spent about an hour scraping sonybond out from around about four components and I can see I'll have to replace at least 7 or 8 jumpers due to corrosion.

It may not work when I'm done, but it will look nice inside darn it.

Someday I'll learn that there's a reason no one else bids on these things.

 

[sunbulls]

At least it doesn't look like they glued down the ends of the small coax jumpers, and your two transformers look clean too. Glue that has dripped down into the transformer windings is difficult to remove. I spent 2 days removing all the Sonybond on a TRC-483 that I restored recently. I even had to use my set of needle size drill bits to clean out the holes before replacing some of the parts. I especially like to restore the older compact CB's that others would otherwise toss. Unfortunately most of them are plagued with Sonybond. To me, it's still worth the effort.

 

[Smokinone]

Nice looking old radio. Hope it works for ya.

I didn't even know Sony made CB radios

 

[sunbulls]

For some reason Sony has never released any technical info on any of their CB radios. At this late date one would think at least some schematics would have been leaked. Why the big secret Sony? I stopped buying all things Sony years ago when they reneged on most of their rebates and guarantees. They’re too big to care I guess.

 

[TM86]

At least it doesn't look like they glued down the ends of the small coax jumpers, and your two transformers look clean too. Glue that has dripped down into the transformer windings is difficult to remove. I spent 2 days removing all the Sonybond on a TRC-483 that I restored recently. I even had to use my set of needle size drill bits to clean out the holes before replacing some of the parts. I especially like to restore the older compact CB's that others would otherwise toss. Unfortunately most of them are plagued with Sonybond. To me, it's still worth the effort.

You're more dedicated than I am. If I can tell that the only thing the glue is making contact with is plastic (like insulation) and the part is difficult to get out, I'll usually leave it be.

As an example, this radio has a toroid choke on the power input that has a plastic cover and the windings have the Sony snot inside. I think that I would most likely irreparably damage the part by trying to clean it out. I did clean the blob that was holding it to the circuit board before it could eat that.

 

[TM86]

I didn't even know Sony made CB radios

I know they made this one and a sideband rig, the ICB-2500.

 

[sunbulls]

You're more dedicated than I am. If I can tell that the only thing the glue is making contact with is plastic (like insulation) and the part is difficult to get out, I'll usually leave it be.

As an example, this radio has a toroid choke on the power input that has a plastic cover and the windings have the Sony snot inside. I think that I would most likely irreparably damage the part by trying to clean it out. I did clean the blob that was holding it to the circuit board before it could eat that.

The plastic sleeve will often pull off easily once the glue on top and bottom is removed. I usually cut around the top with a Xacto knife by carefully separating the glue away from the sleeve. The same sleeve (undamaged) or heat shrink is then reapplied once everything is cleaned. Worse case, I’m not beyond winding a new one.

 

[Smokinone]

For some reason Sony has never released any technical info on any of their CB radios. At this late date one would think at least some schematics would have been leaked. Why the big secret Sony? I stopped buying all things Sony years ago when they reneged on most of their rebates and guarantees. They’re too big to care I guess.

Seems odd that the information wasn't "leaked" from service centers throughout the years. I don't think their CB's were too much of a hit as I've never seen any before, and I've been playing with this stuff for a lot of years. I'm sure it was well built as that's the way they used to do things.

Well SONY isn't what it used to be that's for sure, but I still buy their TV's and have never had any problems. After having issues with some of the other major players over the years, SONY has served me well although I'm sure they haven't hit home with everyone.

 

[TM86]

Finished cleaning out the crud glue and swapping out caps today. Used a makeshift set up to apply power and it lit up. Channel display seems to show all digits and there's static from the speaker.

So I guess it may actually be worth fixing the mic connector and getting a power cord for it that doesn't have a smashed fuse holder. Guess I'll clean the faceplate and knobs as well.

Probably won't be attempting an alignment, though. While there's plenty of stuff to tweak, it would be way too easy to knock it out of whack and I've got no roadmap to put it right if I do that.

 

[TM86]

Replaced the mic connector, so that's all one piece now instead of 4.

Waiting on a new power cord to arrive. This is one of those radios that has the wires hanging out of the back, in case it wasn't obvious from the pics above. I'll reuse the strain relief if I have to and if it survives getting the old power cord out.

Once the new cord is in place I'll feel like it's safe to actually have it powered on for more than a lamp check.

 

[TM86]

Received new cord, wired it in. Radio lights up like it should. Receives on frequency, pretty much, I think, down to about -124 db.

Transmit is a little high, by about 500 HZ or so, but no audio.

And that's when things went sideways.

Built an adapter, I thought, for Uniden 4 pin to the Sony pinout, which is TX on pin 1, return on pin 2, shield on pin 3, and audio on pin 4. Weird, I know. Grabbed a handy Cobra mike, and didn't think about whether it was set up for electronic or relay switching. Magic smoke was then emitted from R188. Which is mostly hidden by a large cap in the pics above.

All I can tell from what's left is the first band is green. It reads 5.1 Ohms out of circuit, but I don't know if it's supposed to, or if it should be 5.1K Ohms, etc. So, now I'm stuck until someone can post a pic of that area of the radio or upload a schematic.

There is a place online that claims to have the service manual for this radio for just 25 bucks, but I don't trust them.

 

[TM86]

Took a chance and ordered a 5.1 Ohm 1/2 watt resistor. Figured the worst that could happen is it breaks the radio. Put the new resistor in and the radio seems to be working as well as it was before I burned the original up. Keys up with the same carrier level, at least.

Which leaves me with the no transmit audio problem. Which is most likely what originally sidelined this radio. No audio in PA mode, either. So it's consistently bad.

I suspect the mic element, but I don't have a sacrificial spare to test that theory. Going to have some fun tracing out connections so I can figure out where the mic amp is and if it has any input or output.

 

[Dmans]

I don't have a sacrificial spare to test that theory

I would try my audio generator hooked directly to the mike connector---if it were me.

Good Luck
73
David

 

[TM86]

I would try my audio generator hooked directly to the mike connector---if it were me.

You're assuming I'm bright enough to have built or bought one, which isn't supported by the evidence. Maybe once the holiday bills are paid off. OK, you can stop laughing.

What I have done is take the mic element out and take a reading. Open circuit, or somewhere north of 1,000 M Ohms, anyways. From the looks of it, should be about the same as you'd find in a Cobra radio of the era, about 600 Ohms or so.