2950, 2970, 2527, DX22b etc. (ept295013z) mods
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2950, 2970, 2527, DX22b etc. (ept295013z) mods
Receive:
Change C45 and C48 to 2.2uF mylar or non-polarized electrolytic
Remove C47
Change C224 to a 2.2uF, 25 volt electrolytic or Tantalum. Observe polarity
Change C221 and C222 to 2.2uF mylar or non-polarized electrolytic
Transmit:
Change C155 and C141 to 10uF, 16 volt Tantalum. Observe polarity
Change C240, C298 and C299 to 2.2uf mylar or non-polarized electrolytic
Sideband/FM Transmit:
Change C131 and C136 to 2.2uF mylar or non-polarized electrolytic
Note: For the transmit to have full width, the audio in/out wires on the echo board (one wire from J2 and one from J3) have to be disconnected and jumped together, bypassing the echo board.
Change C45 and C48 to 2.2uF mylar or non-polarized electrolytic
Remove C47
Change C224 to a 2.2uF, 25 volt electrolytic or Tantalum. Observe polarity
Change C221 and C222 to 2.2uF mylar or non-polarized electrolytic
Transmit:
Change C155 and C141 to 10uF, 16 volt Tantalum. Observe polarity
Change C240, C298 and C299 to 2.2uf mylar or non-polarized electrolytic
Sideband/FM Transmit:
Change C131 and C136 to 2.2uF mylar or non-polarized electrolytic
Note: For the transmit to have full width, the audio in/out wires on the echo board (one wire from J2 and one from J3) have to be disconnected and jumped together, bypassing the echo board.
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- Goldfinger
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- Goldfinger
- Site Maintenance
- Posts: 3860
- Joined: Sat Jun 30, 2007 12:27 am
- Location: Beaver State
- Goldfinger
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- Joined: Sat Jun 30, 2007 12:27 am
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
What effect would swapping out the stock 455ht filter to a 455f that is 6Khz?
- Goldfinger
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
You will just have crisper highs from the added high end response. On 29's, I also noticed the lower bass seems cleaner when you compare a wide radio with the stock filter to one with a 6kc. (when listening to a wide transmitter)
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Goldfinger, I am sure this has been asked before. Can you use NON-polarized 2.2uf in place of the polarized 2.2uf? Thanks!
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
I've never done it on a CB but I'm sure you can. Just make sure they are 25 volt or higher.
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
What's the injection stops for this board thank you, for am and ssb
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Is the injection cap a 2.2uf or 10 if and witch side the cap do ya inject threw .
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Use a 10uF into the R281/R282 end of C299.
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
I used a 2.2 uf but there some feed back over the recive . I wonder if a 10 uf would stop that .
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
It's virtually impossible for the direct injection on a Galaxy/Ranger to feed back into the receive unless you aren't injecting in the right place. Are you sure the radio you are working on has the ept295013z board?
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Galaxy saturn turbo that has the 2950 orange face board .
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
C299 farthest away from the case with a 2.2uf 50v cap
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Pull out C298 and see if it stops.
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
You said c298
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Yes, i wanted to see if the audio was back-feeding either through the mic amp or the talkback circuit.
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Removed the cap like suggested and no more feedback over speakers .
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Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
It looks like something is funny with the talkback circuit or something. With that cap removed you won't be able to use the mic jack for modulation but if you are direct injecting, it won't matter.
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