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<div class="moz-cite-prefix">There are some options....<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.repeater-builder.com/hamtronics/ta-51pl_mod.html">http://www.repeater-builder.com/hamtronics/ta-51pl_mod.html</a><br>
This modification was originally written to allow PL to be
transmitted at industry standard levels. Using this modification,
with a suitable varactor, will provide full voice deviation of 5
kHz. This works well on a TA451 because of the multiplication
factor of 36. This modification converts the transmitter from PM
to FM. You'll need to pre-emphasize and limit in software. This
gives the best sounding audio from an older Hamtronics exciter.
Use only on ham bands - modification is not commercial use
accepted. <br>
<br>
<a class="moz-txt-link-freetext" href="http://www.repeater-builder.com/hamtronics/ta-51altaudio.html">http://www.repeater-builder.com/hamtronics/ta-51altaudio.html</a><br>
Similar to what Robert mentioned, and should be fine as long as
you are limiting without pre-emphasis in software. Use only on
ham bands - modification is not commercial use accepted.<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.repeater-builder.com/hamtronics/pdf/COR-3.pdf">http://www.repeater-builder.com/hamtronics/pdf/COR-3.pdf</a><br>
Look at the circuitry associated with Q1 and Q2. <br>
<br>
Kevin<br>
<br>
<br>
<br>
<br>
On 3/8/2014 11:37 AM, Robert A. Poff WB3AWJ wrote:<br>
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<div>I would think that it should switch 100ma with no problem.<br>
</div>
<div>Make sure you put a diode across the relay coil (band
toward + volts) to suppress back emf when the relay releases.<br>
</div>
<div><br>
</div>
<div>As to the Hamtronics exciter....<br>
</div>
<div><br>
</div>
<div>I had to use one (TA451) on a local club UHF repeater that
I redid as an Allstar node. That repeater always had sounded
horrible before.<br>
</div>
<div>And to no surprise, with the Allstar node it sounded
absolutely RANCID. I needed to bypass all the mic processing
and the really nasty clipper,<br>
</div>
<div>and inject the transmitter audio downstream just after the
splatter filter, and essentially directly into the phase
modulator. Through an isolation <br>
</div>
<div>resistor (somewhere around 4.7K if I remember correctly).<br>
</div>
<div><br>
</div>
<div>Now it sounds as smooth as my Mastr II / Allstar repeaters
do.<br>
</div>
<div><br>
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data-mce-style="color: #000; font-weight: normal; font-style:
normal; text-decoration: none; font-family:
Helvetica,Arial,sans-serif; font-size: 12pt;"><b>From: </b>"Bryan
Fields" <a class="moz-txt-link-rfc2396E" href="mailto:Bryan@bryanfields.net"><Bryan@bryanfields.net></a><br>
<b>To: </b>"app rpt-users" <a class="moz-txt-link-rfc2396E" href="mailto:app_rpt-users@ohnosec.org"><app_rpt-users@ohnosec.org></a><br>
<b>Sent: </b>Friday, March 7, 2014 5:44:12 PM<br>
<b>Subject: </b>[App_rpt-users] RTCM PTT circuit<br>
<div><br>
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I'm interfacing the RTCM with a hamtronics exciter and will be
using a small<br>
relay to key it. <br>
<div><br>
</div>
Can it sink 100 ma to ground for the relay or do I need a
driver transistor?<br>
<div><br>
</div>
-- <br>
Bryan Fields<br>
<div><br>
</div>
727-409-1194 - Voice<br>
727-214-2508 - Fax<br>
<a class="moz-txt-link-freetext" href="http://bryanfields.net">http://bryanfields.net</a><br>
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