Cobra 2000 GTL Hi-Fi questions:

[Hawkeye351]

Took the recap great. All caps, even the 50v caps.
Took the realignment great. Receive is amazing now. Beautiful sounding receive.
Limiter back in place.
R131 back in place.
No audio mods/hacks anymore.

AM swings to around 20w PEP (14w peak) with variable key turned wide open (6w). Swings to 9w average.
Sidebands are doing around 15w now.

Now on to the Hi-Fi cap changes.

Someone previously stated I should stick with the lower values indicated by the gold finger mods.

So, in cases where gold finger has two values indicated that could be used, I should stick with the lower of the two values?
And just stick with the single values that are listed with just one value?
Sorry for sounding stupid. It's just that this Hi-Fi stuff is new to me. I've never did this mod before, not sure what to expect.

 

[Shadetree Mechanic]

Well, here's what I am thinking. When my radio was done, I had all the audio done which included the mic jack audio. But this made using a hand mic useless because it needed an equalizer. So I ended up putting the mic audio back to stock and everything past the direct inject point was left Gold Finger. This way I could get the best of both worlds. And it is a fairly good compromise, but only certain hand mics that have no low end will work.

 

[nomadradio]

I could strap a 1k ohm resistor across the drain and source pins of FET2 and improve receive sensitivity?

Yes, and you would be defeating the AGC as well. Wherever it mentioned the S-meter resting above zero, this would drive the meter back to the zero point. Not a fix, just a diagnostic tweak.

73

 

[Cable Guy]

So, in cases where gold finger has two values indicated that could be used, I should stick with the lower of the two values?
And just stick with the single values that are listed with just one value?

For instance, gold finger specifies change c108 to a 1uf to 2.2uf tantalum. C108 is a stock .47uf, so he indicates increasing. I start at the value closest to stock, (the 1uf is closer to .47uf than the 2.2uf) and increase or decrease in the same direction until it sounds right. You likely won't notice a single cap change, until the whole path is able to pass the audio you want.

That's why I do all cap changes, with the closest to stock when given a choice, to get the entire path passing. Then check it out. It might sound great, but you might wish for more bass on tx, okay, increase the tx side caps some, the ones you went easy on, the 1uf to 2.2uf scenario.

I think once you try it, and if you do it right, it can be very rewarding, I think you'll be looking to goldfinger everything.

Edit; my notes say that when changing c101 to a 1.5uf tantalum, I lost tx audio. I used an electrolytic instead and that fixed it. Not sure why.

 

[Hawkeye351]

Not finished with this radio yet. Had to jump on something else. Gonna try to get back on it tomorrow or Tuesday.