rci 2970n2
rci 2970n2
I found the post where Goldfinger told someone which caps to parallel with larger value non-SMT (modder beware of course) for the 2995 DX. I'd like to try something similar to open up the lower end of the TX of a rci 2970n2 (I'm using a Drake R8B as a separate receiver which already does 6k beautifully)
From the specs on the 2995dx (can't imagine the 2970n2 would be too terribly different, although I hear its a different board) is 400hz-5000hz on AM TX. 5khz for a high end isn't bad for stock. If you could just get the low end down to 75-100 or so...
From the specs on the 2995dx (can't imagine the 2970n2 would be too terribly different, although I hear its a different board) is 400hz-5000hz on AM TX. 5khz for a high end isn't bad for stock. If you could just get the low end down to 75-100 or so...
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- Goldfinger
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Sorry 479tx, I musta let this thread slip my mind back in September. If it's the same as a 2995:
Receive:
C87: change to a 1-2.2uF mylar or non-polar electrolytic
C47: make smaller for more highs.
C48: 1-2.2uF
C193: 1-2.2uF
Transmit:
C163: Change to a 10uF Tantalum (observe polarity)
C199 and C262: change to 2.2uF mylar
Receive:
C87: change to a 1-2.2uF mylar or non-polar electrolytic
C47: make smaller for more highs.
C48: 1-2.2uF
C193: 1-2.2uF
Transmit:
C163: Change to a 10uF Tantalum (observe polarity)
C199 and C262: change to 2.2uF mylar
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To those that are curious,
You can (if you are careful, and have a steady hand) solder light weight poly or tant caps across the existing caps you're supposed to change (shorten the leads, and bend them like a U shape) with good results!
I didn't feel comfortable removing the existing SMT components but this works just as good.
You can (if you are careful, and have a steady hand) solder light weight poly or tant caps across the existing caps you're supposed to change (shorten the leads, and bend them like a U shape) with good results!
I didn't feel comfortable removing the existing SMT components but this works just as good.
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Re: rci 2970n2
Are ceramic smt cap ok in place of the mylars?
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Re: rci 2970n2
Yes, for the hifi conversion, the uF value is whats important not the style of cap. SMT would be better as it will solder in more securely than grafting in a discrete component.
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Re: rci 2970n2
Hello GoldFinger! I was curious if you studied making any changes in the modulator section?
Thanks in advance!
Thanks in advance!
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Re: rci 2970n2
Yes, in 2014 when I posted this mod I didn't know about the cap change on the modulator circuit yet.
Change C260 to a 330uF, 16V (or greater)
If this cap isn't changed, there will be roll-off below 100hz.
Change C260 to a 330uF, 16V (or greater)
If this cap isn't changed, there will be roll-off below 100hz.
wwpdx
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