September 22nd 07, 02:33 PM
posted to rec.radio.cb,rec.radio.amateur.equipment,rec.radio.amateur.homebrew
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First recorded activity by RadioBanter: Jul 2006
Posts: 985
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What happened to the SkyWave 2879ABTC?
On Sep 21, 11:45 pm, Frank Gilliland
wrote:
On Fri, 21 Sep 2007 07:37:54 -0700, Telspam Electronics
wrote in
.com:
On Sep 20, 10:48 pm, Frank Gilliland
wrote:
On Thu, 20 Sep 2007 17:08:23 -0700, Telstar Electronics
wrote in
. com:
On Sep 20, 3:03 pm, wrote:
Oh...your bias is magical? It uses no components for compensation?
I always suspected your design to be that of an imaginary nature.
Not magical... it used the base-emitter voltage drop of an MJE3055T
(mounted directly to heat sink) to track with the 2SC2879 power
transistors. Since it used a transistor with gain... it worked so much
better than just a plain old diode on the sink for tracking. It worked
fantastic...
How well it works depends on how well you hacked the design from this
link I posted (while pointing out some of the many problems with your
earlier splatterbox):
http://www.ifwtech.co.uk/g3sek/tr-bias/tr-bias1.htm
I was able to set set class AB bias ( I chose about
200Ma) on the power transistors... and hold +/-5% collector current
changes from -40 to +100C heat sink temp during amp operation.
That's interesting. Previously you said your bias scheme can "hold the
500mA bias to 10% from -30 to +85C". It's funny how many times you
have changed the specs. I especially enjoyed the time when you changed
the power output specs three times in one week after you were caught
fabricating them instead of actually measuring them. Oh well, such is
the life of an internet-educated hack.
But alas, there's still one unresolved issue here, Brian.... where's
the schematic?
Glad you're back Frank...
I never left, Brian.
your always good for a laugh.
I'm glad you're amused. But don't you think it's time for you to get a
job and relieve the financial burden on your parents and the Illinois
welfare system? If I lived in that state I would be outraged that you
are leeching my hard-earned tax dollars, but I don't. I guess people
over there prefer to coddle malingering basement-dwellers. You are
certainly lucky to live in a place with such generous folks, Brian.
Over here on the left coast you would have to support yourself with
gainful employment. And I hope that gives you something else to laugh
about, cause the thought of you actually working for your keep sure
leaves -me- ROTFLMMFAO!!!
BTW, where's that schematic?- Hide quoted text -
- Show quoted text -
Keep up the amusing posts Frank...
www.telstar-electronics.com
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