Path: csiph.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: "Carlos E. R." Newsgroups: comp.os.linux.misc Subject: Re: High-Gain Mic Amplifier - Hard-Wired Input - Anyone SEEN These ? Date: Mon, 14 Sep 2026 09:44:12 +0200 Lines: 58 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: individual.net hP33T6hNMshdc0MNBJdlNgUEwb1fOtco2XzcJ3tVoS6PN52J8+ Cancel-Lock: sha1:onjfgYiTE2te2rKtb+M1IWP6VaE= sha256:SXmThGx3e3JDterWGEONWp+doAF6GTulR7yeQ5Hkeek= User-Agent: Mozilla Thunderbird Content-Language: en-GB In-Reply-To: Xref: csiph.com comp.os.linux.misc:91417 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🇪🇺.