[MRCA] H-250 Audio Amp Weekend Project

[Rich Arland]

Actually, Breck, we QRPers used coffee cups (the bigger ones from QT or Race Track) and cut them down until they resonated at 550-650Hz. They were better than a lot of the "active" AF filters on the market in 1980! There is an article in the QRP Quarterly about these cheap and easy AF filters somewhere, provided I can find it!

Vy 73

Rich  K7SZ



________________________________
From: mrca-bounces at mailman.qth.net <mrca-bounces at mailman.qth.net> on behalf of Gene Smar via MRCA <mrca at mailman.qth.net>
Sent: Monday, August 3, 2020 5:57 PM
To: 'Military Radio Collectors Association' <mrca at mailman.qth.net>
Subject: Re: [MRCA] H-250 Audio Amp Weekend Project


Kinda reminds me of the Acoustic Attenuator a co-worker and I built when we were working at the local electric utility as summer students.  The RJE printer, a model ASR-33 IIRC, was right next to our desks.  When it printed our results, it clattered and clacked for ten minutes at a time.  We found a cardboard box that held fanfold paper (remember that stuff?) and stuffed it with newspaper (remember that stuff?) around the inside edges and inverted it over the printer.  Musta attenuated the acoustics by 20 dB or better.



Nice job, Breck.





73 de

Gene Smar  AD3F



From: mrca-bounces at mailman.qth.net [mailto:mrca-bounces at mailman.qth.net] On Behalf Of Alex J Rokowetz via MRCA
Sent: Monday, August 03, 2020 4:34 PM
To: Military Radio Collectors Association <mrca at mailman.qth.net>; B. Smith <smithab11 at comcast.net>
Subject: Re: [MRCA] H-250 Audio Amp Weekend Project



Where is the gain dial?



K2AJR



Alexander J Rokowetz

(516) 551-2498

belarok at yahoo.com<mailto:belarok at yahoo.com>

https://www.linkedin.com/in/alexanderrokowetz/







On Monday, August 3, 2020, 02:42:07 PM EDT, B. Smith <smithab11 at comcast.net<mailto:smithab11 at comcast.net>> wrote:





Was checking out radio accessories and equipment on my M151A1 and ran across my mini amp.
A simple weekend project and really helps that H-250 receive element in a noisy environment.
Z
[cid:image001.jpg at 01D669BF.2801E090]

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