[Milsurplus] 12BY7 with tiny crystals?

[Jim Whartenby]

DavidWhat crystal frequency or range of frequencies will float your boat?
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.  Murphy

-----Original Message-----
From: Mike Feher <n4fs at eozinc.com>
To: 'David Stinson' <arc5 at ix.netcom.com>; 'milsurplus at mailman' <milsurplus at mailman.qth.net>
Sent: Fri, Jun 3, 2022 9:34 pm
Subject: Re: [Milsurplus] 12BY7 with tiny crystals?

<!--#yiv5495206661 _filtered {} _filtered {}#yiv5495206661 #yiv5495206661 p.yiv5495206661MsoPlainText, #yiv5495206661 li.yiv5495206661MsoPlainText, #yiv5495206661 div.yiv5495206661MsoPlainText {margin:0in;font-size:11.0pt;font-family:"Calibri", sans-serif;}#yiv5495206661 span.yiv5495206661PlainTextChar {font-family:"Calibri", sans-serif;}#yiv5495206661 .yiv5495206661MsoChpDefault {font-family:"Calibri", sans-serif;} _filtered {}#yiv5495206661 div.yiv5495206661WordSection1 {}-->From all I read on different reflectors, the HC-49s tend to crack in most tube circuits. They were really intended for SS stuff. 73 – Mike   Mike B. Feher, N4FS89 Arnold Blvd.Howell NJ 07731848-245-9115  -----Original Message-----
From: milsurplus-bounces at mailman.qth.net <milsurplus-bounces at mailman.qth.net> On Behalf Of David Stinson
Sent: Friday, June 3, 2022 10:02 PM
To: milsurplus at mailman <milsurplus at mailman.qth.net>
Subject: [Milsurplus] 12BY7 with tiny crystals?    Have any of you tired to use the little, short and oval "half size" HC-49S crystals in their DX-100 or other similar rig?These are the tiny things you see in those inexpensive "QRP" kits on Amazon.  I ask because I'm working 20 minutes here, an hour there to get a Bendix 430 fishing boat radio running. "Stock" uses HC-6 xtals.  https://photos.app.goo.gl/FyLFwDbMXvWnCtCe6  The little "shorties" won't give enough drive to run the Bendix circuit:  https://photos.app.goo.gl/QXfQXAVjrtf1WosL6  No buffer or multiplier here. Note the crystal is between the plate and signal grid and has 310V B+ on it.  Here is the DX-100 transmitter circuit, minus the crystal switch and clamper. The crystal is between the signal grid and the screen grid- a variation of the Electron Coupled?  https://photos.app.goo.gl/vfi99ePHKKk6vGHz7  I'm wondering if the 12BY7 in the DX-100 configuration would perform better with the "shortie" crystals than the Bendix circuit. What do you think?  TNX OM ES 73 DE Dave AB5S
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