IF can wanted

[w2amr]

I am restoring an old RCA CB rig. I found a short in one of the IF's and I can't fix it. Anybody have one laying around. It is 1650 KC's
rca if can.jpg

[N8YX]

Found this on eBay. Pricy but it'll work:

http://www.ebay.com/itm/Miller-1650-.../361395778911?

[w2amr]

Found this on eBay. Pricy but it'll work:

http://www.ebay.com/itm/Miller-1650-.../361395778911?

Tnx Fred, but the whole radio isn't worth that. The problem is, one of the flat silver mica caps in the bottom of the IF is bad. I have seen online where you can repair them by drilling out the rivet , bypassing the cap, then put a replacement mica on the leads under the chassis when the IF is reinstalled. Trouble is, I don't know what value to use , and it isn't marked on the schematic.

[N8YX]

Tnx Fred, but the whole radio isn't worth that. The problem is, one of the flat silver mica caps in the bottom of the IF is bad. I have seen online where you can repair them by drilling out the rivet , bypassing the cap, then put a replacement mica on the leads under the chassis when the IF is reinstalled. Trouble is, I don't know what value to use , and it isn't marked on the schematic.

Got access to a dip meter or network analyzer? LCR meter? Pull the old cap, measure the inductance of the coil with the slugs inserted halfway...then solve for "C" at 1650KHz. Get something close, tack it in then dip the tank and check resonance.

I've had to do this many times when adding WARC bands to older Kenwood and Yaesu rigs...build your own RF and IF stage peaking coils or transformers, VCO coils and whatnot.

Let me know what you need in the way of silver mica caps if your junk box is low on them.

[N8YX]

Did you see this, George?

http://www.surplussales.com/Inductor...SmAdjRF-1.html

[w2amr]

Got access to a dip meter or network analyzer? LCR meter? Pull the old cap, measure the inductance of the coil with the slugs inserted halfway...then solve for "C" at 1650KHz. Get something close, tack it in then dip the tank and check resonance.

I've had to do this many times when adding WARC bands to older Kenwood and Yaesu rigs...build your own RF and IF stage peaking coils or transformers, VCO coils and whatnot.

Let me know what you need in the way of silver mica caps if your junk box is low on them.

Here is a close up of the caps Fred. they are flat wafers built into the bottom of the IF, held together with a rivet. cap close up.jpg

[N8YX]

Is that cap showing shorted, George?

One other thing I found whilst cruising the 'Net for a solution...a good bit of 60s and 70s era gear used 1650KHz as an IF. Many Hallicrafters SX/S SW receivers, Lafayette CB rigs, Codan HF SSB maritime transceivers...know where any of these might be hiding?

ETA: Look here: http://www.ebay.com/itm/Hallicrafter...item3ab119f900

Will those work? I don't have an S-94 schematic handy to check.

[w2amr]

Is that cap showing shorted, George?

One other thing I found whilst cruising the 'Net for a solution...a good bit of 60s and 70s era gear used 1650KHz as an IF. Many Hallicrafters SX/S SW receivers, Lafayette CB rigs, Codan HF SSB maritime transceivers...know where any of these might be hiding?

Yeah, somehow it's shorting the top coil to the bottom one. If I can't fix this one, I'll have to keep an eye out for a junker that uses a 1650 IF. This is an RCA mark 7 which is almost the same radio as a Lafayette HE20. I have 3 Mark 7s now. One I restored and converted to 10 meters, the second one was my uncles who bought it new in 1960. I'm restoring that now for the CB. The 3rd one I just picked up on E-bay. It worked for about 15 minutes before the IF took a dump. Oh well, If I can't fix it , I'll have a good parts rig for the other two.

[K4PIH]

I have an old rca cb that I'll check and get back with you tomorrow eve. If I have a match you can have the whole radio. Pm your address if you want.

73 PIH

[w2amr]

I have an old rca cb that I'll check and get back with you tomorrow eve. If I have a match you can have the whole radio. Pm your address if you want.

73 PIH

Great, thanks!