Cobra 148 MK2 10Khz off All Bands

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currentstatus
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Re: Cobra 148 MK2 10Khz off All Bands

Post by currentstatus »

Kaliphan wrote: 04 Jun 2018, 21:20 Please, measure the 15MHz signal, I think you should be able to at the junction of C94/R131.

KC at 12, FM.

Once we know what that's doing we can give you more advice
I don't see c94.. but hot side of R131 is showing 16.4985 (which is what I'm getting on TP-3).
And that's as close to 16.4900 as I can get before it falls off.
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Otter
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Re: Cobra 148 MK2 10Khz off All Bands

Post by Otter »

Just sent it to Nick for fixing, with the original crystals. a 15MHz crystal from Farnell won't work properly.
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sonoma
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Re: Cobra 148 MK2 10Khz off All Bands

Post by sonoma »

Make sure you get info from the repair guy so we will know just what was wrong.. this one I have followed and am stumped with your problem.
Kaliphan
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Re: Cobra 148 MK2 10Khz off All Bands

Post by Kaliphan »

Otter wrote: 04 Jun 2018, 22:33 Just sent it to Nick for fixing, with the original crystals. a 15MHz crystal from Farnell won't work properly.
I think that's the best bet now, all the messing about trying to realign it is causing more problems and just confusing the issue, there is nothing wrong with the original crystals, I think it is a partially removed mod and the VCO being adjusted to lock with a misaligned loop crystal. we are beyond what can be easily done on a forum and need hands on now.
currentstatus
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Re: Cobra 148 MK2 10Khz off All Bands

Post by currentstatus »

Yes agree.. I've put it to one side for now.. bit of a head wreck!
But the whole point of posting was to get advice and to learn from other experienced users.. which I'm grateful for!

Thanks guys..
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