Re: W0RW @ Ice Station Zebra, 25 Jan. 20, 1800z


John - KK4ITX
 

PAUL,

That is a great looking project, love this part of the hobby maybe even more than piling up QSOs !  Having a problem and fixing it is almost as rewarding as the completed project.

I assume that you plan to be back on the air with the rig on FEBRUARY 5 ?

I ‘ll give a listen down here in Florida.

73,

John
KK4ITX 

Visit:  www.zaarc.org.   👁

On Feb 3, 2020, at 19:06, w0rw <w0rw1@...> wrote:

After the Winter FD Ops at Ice Station Zebra,
Don, AA6GA, told me that i was not responding to some calls on 7032 kHz.
i checked my BC-221 and found that my transmit frequency was 400Hz lower than my receive frequency. So the only guys i worked were those who didn't zero beat me.
i was not 'transceiving', i was working 'split'.
The base transceiver i am using in my Re-Purposed BC-221 is the '1 Watter'.

i checked out the 1 Watter and found that the 10V regulator (U1, 78L10) on the VXO was not regulating well enough. i tried 3 different 78L10's but they were all inadequate to regulate the 10v line. My 12V battery was dropping down too close to the top requirement of the 10V regulator.
So i replaced U1 with a LM2940T-10, 1A, 10V, Low Drop Out regulator in a TO-220 package.
It also has a 22MF capacitor on the output.
The LDO regulator will keep working as my battery discharges.
(ps: My 'Tune' pot is 50K ohms).
Now  my RX freq is the same as my TX freq. My 10V line is steady now.
i will be back on the air with the BC-221 again testing it on   5 Jan  2020, 1600z, 7032 kHz.
So if you called me and i didn't answer, here is your chance to get your special "Dino" QSL card. 

The description of my Re-Purposed BC-221 is in the  NAQCC Newsletter: 

  "A Skin Deep BC-221", 

http://naqcc.info/newsletter/newsletter_257.pdf

Paul   w0rw

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