Search found 684 matches

by Goldfinger
Mon Mar 07, 2022 8:38 am
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Road Devil Astatic Help Me Goldfinger
Replies: 4
Views: 419

Re: Road Devil Astatic Help Me Goldfinger

The circuit already looks pretty wide but changing the cap and that resistor in the feedback circuit should help a little. If it's still lacking lows it might just be the mic element.
by Goldfinger
Sat Mar 05, 2022 9:19 am
Forum: rx and tx mods
Topic: Kenwood TS440s request
Replies: 4
Views: 359

Re: Kenwood TS440s request

I think I finally found a schematic/service manual that's somewhat readable. It'll take awhile to look at so be patient. (I wish these jokers would scan the PDF's with higher resolution.) I mean if you are going to take the time to actually scan the book, it doesn't cost any more to scan at 200DPI i...
by Goldfinger
Thu Mar 03, 2022 9:32 pm
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Road Devil Astatic Help Me Goldfinger
Replies: 4
Views: 419

Re: Road Devil Astatic Help Me Goldfinger

Change C5 to a 4.7uF electrolytic, observe polarity.
Change R5 to a 47K
by Goldfinger
Sat Feb 26, 2022 5:52 pm
Forum: rx and tx mods
Topic: Request - Stryker 955 cap mods
Replies: 26
Views: 7452

Re: Request - Stryker 955 cap mods

Pics are always OK. Thanks FRED.
by Goldfinger
Sat Feb 26, 2022 9:57 am
Forum: rx and tx mods
Topic: Request - Stryker 955 cap mods
Replies: 26
Views: 7452

Re: Request - Stryker 955 cap mods

Great FRED, I've been waiting for one to come across my bench so I could physically see it in front of me and then put the info here. Your info should help a lot, thanks. :mrgreen:
by Goldfinger
Tue Feb 15, 2022 9:48 am
Forum: rx and tx mods
Topic: Request - Stryker 955 cap mods
Replies: 26
Views: 7452

Re: Request - Stryker 955 cap mods

Here is the layout:
Stryker SR-955 HPC Board_Layout_Top(1).pdf
(1.42 MiB) Downloaded 221 times
by Goldfinger
Tue Feb 01, 2022 9:14 am
Forum: rx and tx mods
Topic: Royce Model 1-678 schematic & mods?
Replies: 8
Views: 569

Re: Royce Model 1-678 schematic & mods?

Like an O2A AM Midland chassis, the mic doesn't have it's own amplification stage. The only place you can raise the mic gain will also raise the receive audio gain.
You could make R310 a little lower in value and see if that helps.
by Goldfinger
Sun Jan 23, 2022 8:57 am
Forum: rx and tx mods
Topic: Anytone AT-6666 (Quad 6) hifi
Replies: 18
Views: 3250

Re: Anytone AT-6666 (Quad 6) hifi

Yes, there is a few guys modding these radios so thanks for posting up the info and the pics. I can't because I'm too old and my eyes are no good any more. Yeah, the schematics I provided above were ones I grabbed a few months ago and since then I've seen some others floating around. My initial cap-...
by Goldfinger
Fri Jan 21, 2022 9:17 am
Forum: rx and tx mods
Topic: Anytone AT-6666 (Quad 6) hifi
Replies: 18
Views: 3250

Re: Anytone AT-6666 (Quad 6) hifi

Thanks for your info and for taking the time to post the results, much appreciated.
by Goldfinger
Thu Jan 20, 2022 2:49 pm
Forum: rx and tx mods
Topic: Anytone AT-6666 (Quad 6) hifi
Replies: 18
Views: 3250

Re: Anytone AT-6666 (Quad 6) hifi

Great, thanks for the update.
by Goldfinger
Fri Jan 14, 2022 9:52 am
Forum: rx and tx mods
Topic: Anytone AT-6666 (Quad 6) hifi
Replies: 18
Views: 3250

Re: Anytone AT-6666 (Quad 6) hifi

Anytime. If you come up with any real-world results and would like to post them up here, feel free. It's always nice to have an "experiment pioneer" post up results of audio chain tinkering. :mrgreen:
by Goldfinger
Thu Jan 13, 2022 6:08 pm
Forum: rx and tx mods
Topic: Anytone AT-6666 (Quad 6) hifi
Replies: 18
Views: 3250

Re: Anytone AT-6666 (Quad 6) hifi

It looks like C542 and C500 are adding a small amount of feedback only at the upper extreme in frequency. Changing the value will move around the shelving frequency. As they are small in value (picofarads) you would probably get a lot of change with small changes in value. These caps would be the on...
by Goldfinger
Tue Jan 11, 2022 11:32 am
Forum: rx and tx mods
Topic: Royce Model 1-678 schematic & mods?
Replies: 8
Views: 569

Re: Royce Model 1-678 schematic & mods?

Royce 1-678 hi-fi RX : C207: Change to a 1uF polyester/mylar/NP electrolytic CM23: Change to a 1uF or 2.2uF polyester/mylar/NP electrolytic TX and RX : C310: Change to a 2.2uF polyester/mylar/NP electrolytic C306, C304 Change to 2.2uF 16V tantalum or electrolytic, observe polarity CM7: Change to a 1...
by Goldfinger
Fri Jan 07, 2022 9:58 pm
Forum: rx and tx mods
Topic: Royce Model 1-678 schematic & mods?
Replies: 8
Views: 569

Re: Royce Model 1-678 schematic & mods?

I dug out the SAMS and scanned it! :mrgreen:
Scanned at 200dpi
Royce 1-678 SAMS.zip
(10.89 MiB) Downloaded 374 times
Anyone feel free to share this anywhere.

Image
by Goldfinger
Tue Jan 04, 2022 6:31 pm
Forum: rx and tx mods
Topic: Royce Model 1-678 schematic & mods?
Replies: 8
Views: 569

Re: Royce Model 1-678 schematic & mods?

Darn, I found SAMS 171 with the 1-658 in it which is even closer to the 1-678 in features.
by Goldfinger
Sun Jan 02, 2022 8:43 pm
Forum: rx and tx mods
Topic: Royce Model 1-678 schematic & mods?
Replies: 8
Views: 569

Re: Royce Model 1-678 schematic & mods?

I have all of the SAMS books but the problem is that since I moved in 2007 most of them are buried. I have all of the ones handy for popular radios but not the rest. I did find SAMS 175 that has the 1-675 Module Transceiver but not SAMS 172 that has the 1-678 Module Transceiver. The 1-675 looks simi...
by Goldfinger
Sun Oct 31, 2021 3:31 pm
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Pearce-Simpson Tiger 40
Replies: 2
Views: 773

Re: Pearce-Simpson Tiger 40

TX:

Change C81 to a 1uF mylar, poly or non-polarized electrolytic



RX:

Change C75 to a 2.2uF mylar, poly or non-polarized electrolytic



RX and TX:

Change C83 to a 2.2uF mylar, poly or non-polarized electrolytic
Change C94 to a 1000uF, 25 volt electrolytic. Observe polarity
by Goldfinger
Sun Oct 31, 2021 3:18 pm
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Emperor 5010
Replies: 7
Views: 583

Re: Emperor 5010

Awesome! :mrgreen:
Thanks for the update.
by Goldfinger
Sun Oct 24, 2021 9:45 am
Forum: rx and tx mods
Topic: Galaxy 66v2 66v3 tx and rx mods request
Replies: 1
Views: 1305

Re: Galaxy 66v2 66v3 tx and rx mods request

Hey Truck!

If you can direct me to a readable schematic I'd be glad to help you out. The only similar one I can find is the Superstar 240 but the schematic is blurry.
by Goldfinger
Tue Oct 05, 2021 8:46 am
Forum: rx and tx mods
Topic: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Replies: 24
Views: 8350

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.
by Goldfinger
Fri Oct 01, 2021 7:40 pm
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Emperor 5010
Replies: 7
Views: 583

Re: Emperor 5010

You bet!
Good luck and let us know how it works. :mrgreen:
by Goldfinger
Fri Oct 01, 2021 7:12 pm
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Emperor 5010
Replies: 7
Views: 583

Re: Emperor 5010

TX: Change C169 and C233 to 2.2uF - 16 volt or higher, observe polarity Change C234 to a 2.2uF - 16 volt or higher mylar, poly or non-polarized electrolytic Direct inject: Inject through a 4.7uF to the R274 end of C234. If you use a polarized cap, the + goes towards to board. RX: FM: Change C806 on...
by Goldfinger
Thu Sep 30, 2021 8:10 am
Forum: >>> HIGH FIDELITY AUDIO Q and A <<< POST QUESTIONS AND COMMENTS HERE!
Topic: Emperor 5010
Replies: 7
Views: 583

Re: Emperor 5010

That radio has an odd schematic. Gimme some time to stare at it and I'll get back to you.. :mrgreen:
by Goldfinger
Fri Sep 24, 2021 8:18 am
Forum: rx and tx mods
Topic: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Replies: 24
Views: 8350

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.
by Goldfinger
Thu Sep 16, 2021 9:24 pm
Forum: rx and tx mods
Topic: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Replies: 24
Views: 8350

Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods

Pull out C298 and see if it stops.
by Goldfinger
Wed Sep 15, 2021 12:06 pm
Forum: rx and tx mods
Topic: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Replies: 24
Views: 8350

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?
by Goldfinger
Tue Sep 14, 2021 8:19 am
Forum: rx and tx mods
Topic: 2950, 2970, 2527, DX22b etc. (ept295013z) mods
Replies: 24
Views: 8350

Re: 2950, 2970, 2527, DX22b etc. (ept295013z) mods

Use a 10uF into the R281/R282 end of C299.
by Goldfinger
Tue Sep 07, 2021 8:18 am
Forum: rx and tx mods
Topic: RCI 39 hp plus Cap Changes
Replies: 3
Views: 808

Re: RCI 39 hp plus Cap Changes

Wow, there are NO hits on Google for that board number...
Crazy.
by Goldfinger
Thu Sep 02, 2021 10:48 am
Forum: rx and tx mods
Topic: RCI 39 hp plus Cap Changes
Replies: 3
Views: 808

Re: RCI 39 hp plus Cap Changes

There isn't a schematic for it that I can find and I'm not sure which radio it's similar to on the inside. Lescom did a video on it and even showed the inside but there didn't seem to be an EPT board number visible in his video and it didn't look much like any radio's I've worked on before. It's pos...
by Goldfinger
Wed Aug 18, 2021 8:39 am
Forum: rx and tx mods
Topic: Turner M+3 mic and M+2U
Replies: 21
Views: 5276

Re: turner m+3 mic

For less bass, change C5 to a 1uF or a 2.2uF, 16 volt electrolytic. Observe polarity For more highs, change C6 to a .0047uF ceramic disc or mylar/polyester. One more thing you can try if the first two mods don't get what you want is to shift the feedback center frequency by changing C1 to a .0047uF ...

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