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Re: High-Gain Mic Amplifier - Hard-Wired Input - Anyone SEEN These ?

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On 2026-09-14 08:30, c186282 wrote:
> Radio Shack/Realistic USED to sell these ... a small box
> with a speaker and really high-gain mic input jack. I'd
> put a MAGNETIC pickup on 'em ... used 'em to find noisy
> circuits for embedded devices on vehicles. You could
> just HEAR the static. Very useful !
> 
> Have a newer unit, LOW-gain alas. Can BARELY hear a
> thing even on ultra-noisy wiring.
> 
> CANNOT find anything quite like the old RS unit.
> A lot of 'speaker' things, but mostly intended
> for a wireless mic and ridiculously high output.
> 
> My damned hardwire PHONE doesn't RING anymore.
> They MAY be replacing it with some kind of weird
> VOIP device in a few weeks - HOPE it uses my
> existing WiFi - have a shitload of 'devices'
> that'd have to be re-done otherwise. One or
> two might require LADDERS - NOT good for me at
> my age and condition !
> 
> However MEANWHILE ... my phone DOES know when
> the line goes hot, just doesn't RING. It comes
> all alive, lights, CID, all the good stuff.

My guess is that your phone has a broken bell. Or the equivalent 
circuit. Try to plug another unit.

> 
> My IDEA was to put on one of those magnetic sensors,
> DO have one, on the phone. For sure it'll make
> special noises when the electronics come on.
> Then I can HEAR a call, even if there's no ring.
> 
> The one little amp I have is, alas, NOT very
> sensitive. You can hear a LITTLE noise if you
> like put it right over a rotating fan or the
> like. The old RS unit was MUCH better.
> 
> BUT, going pages down on Amazon, doesn't seem to
> BE an equiv of the RS unit. Some alts are cheap,
> ordered a couple to try, but I have doubts.
> 
> Note, IF you remember, the RS unit was a simple
> grey box with a little speaker and a mic jack.
> Ran on a 9v battery. MAY have been a 9v power
> jack too, don't remember. If not, SOLDER !
> A 9v Ard power supply should work perfectly.
> 
> The big trick is "high gain".
> 


-- 
Cheers,
        Carlos E.R.
        ES🇪🇸, EU🇪🇺.

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High-Gain Mic Amplifier - Hard-Wired Input - Anyone SEEN These ? c186282 <c186282@nnada.net> - 2026-09-14 02:30 -0400
  Re: High-Gain Mic Amplifier - Hard-Wired Input - Anyone SEEN These ? "Carlos E. R." <robin_listas@es.invalid> - 2026-09-14 09:44 +0200

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