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I found an untouched like new Cobra 138XLR, Now What?

Onelasttime

Sr. Member
Aug 3, 2011
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So I tried it out tonight on a make magnet mount K40 on a stock pot with a 108" radial under said stock pot. SWR was 1.2 across all 40 channels.

Wow does it have ears! I was picking up all kinds of skip. Motor Mouth Maul was giving me a solid 5-7db with swing and No Name was giving me a solid 5db. I am in Mid-Michigan. North Carolina was rolling in strong.

I plugged in a NOS Philippines Uniden PC 78XL and while the audio sounded better the signal was much weaker and the meter did not read anything. I suspect the difference in audio quality in spite of less receiver sensitivity was down to speakers!

So I plan on recapping the unit and I might install a Digi-Max lite since I already have a kit laying around.

When I took the cover's off to inspect all of the electrolytic capacitors inside where all marked "Uniden" the old blue colored. It had all of it's original transistors dried paste and all. 2SC1307 final and a bunch of 2SC1419's. The bottom of the board had a tone of bodged but OEM parts so it looks like it had all the service bulletins done to it before it left the factor. I know this one was bought in 1978. I have all of the documentation.

So right now my plan is to look through the parts list that came with it and see what caps I have on hand and order 3 tantalums for it. Nothing is blown so better to keep it that way. I am going to see what I have to replace the questionable and always failure prone 2SC1419's most of the NPN's I have for voltage regulation are HUGE modern parts.

So besides re-cap and replacing those always problematic 2SC1419's is there anything else I should do?

When I fired it up with the Radio Shack 1.5A 12V power supply it came with the channel changer took some use and about 1 minute for all the LED's to light but it finally came to life with a few twists of the dial.

Since it is a uPD858 PLL I like the idea of the huge amount of channels it would gain with the Digi-Max-Lite since I bought it years ago just in case I came across a nice 858 or 002 PLL.

Nothing clipped inside and the factory wax is still in the 54Mhz slug.

If she was not 45 years old I would not touch her but 45 years is a long time for those electrolytics. Amazing the Tantalums are still holding up.

It came with a Cobra C55 Dynamic but it takes one of those old 7V Mercury Batteries. I tossed a stock Uniden 4 Pin mic on it but there was no local traffic just skip so no audio reports.

The case and bezel are an 8.5 to 9 out of 10.

Looking forward to advice and keeping this old beauty going for another 45 years!
 
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Really not much that should be done to it other than what you've got planned. If it was hacked up, maybe, but no need when it's been well taken care of.
 
I thought for sure when I took it out of the ebay box it would either not work or work poorly. When it worked so well I thought for sure it must have been recapped already. Nope. It was shocking to open it up and find a time capsule. This was very well cared for by the original owner.

I guess I have gotten used to things being abused in this hobby and while it had since of use it was clearly never abused.

The OEM box is falling apart and there was no orignal packing like foam or cardboard but it was wrapped in small cell bubble wrap. It came with 100% of the original documentation warranty card, FCC temp license, actual license, parts list, schematic, owners manual, date and amount paid for the unit etc....I even know he owned a Star Duster antenna because all of the documentation for it was in the box.

I bought this and a few other radios when I moved to my current home and I put it in my closet with a lot of other gear and just forgot about it. I have been going through this storage space because I have far too many "things" from radio's, to electronic parts to gun parts. I wanted to catalog electronic parts and reorganize the space. I have 6 NOS or Gently used radio's I forgot I had this one included.

I was up to 4am just playing with it. Had so much fun shooting skip in my living room with an old radio and makeshift indoor antenna!
 

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