[ARC5] Reverse engineeing the BC 456 - carbon microphones

[kn7sfz]

Ah, thanks for the nomenclature.  I see there's a pic of one from last 
year on UK EBay including a small schematic.

Neato!

http://www.ebay.co.uk/itm/Mikrofon-Simulator-SM-30-URM-14-U-S-Property-/161665642681?nma=true&si=sOZryufJjssBAY1p1jrnK9Y3Rk8%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557


Richard kn7sfz




On 3/19/2017 9:11 PM, WA5CAB--- via ARC5 wrote:
> Would that be the SM-30/URM-14?  Handy gadget.  I turned one of them 
> into a carbon microphone tester, complete with bias battery.  The 
> unmodified unit sits between an audio oscillator and the transmitter 
> carbon mic jack.  Has a handy switch across the key line.  And a 
> built-in meter.  I have a reprint of the 6-page manual on it available.
>
> In a message dated 03/19/2017 19:08:02 PM Central Daylight Time, 
> kn7sfz at gmail.com writes:
>> Picture?
>>
>> I'd like to say I've seen one before I pass on......:-)
>>
>> Tnx Wayne,
>>
>> Richard kn7sfz
>>
>>
>> On 3/19/2017 4:58 PM, Robert Eleazer wrote:
>>
>>> By the way, should anyone need one, I have a piece of test equipment 
>>> called a "Microphone Simulator."  I have no idea what it does or why 
>>> it does it..
>>>
>>> Wayne
>>> WB5WSV
>>
>
>
> Robert & Susan Downs - Houston
> wa5cab dot com (Web Store)
> MVPA 9480
>
>
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