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View Full Version : IC-756Pro output "noisy" on a few bands


n7ld
03-07-2007, 02:16 AM
Hello everyone.

I've got a problem with the 756Pro where the output power is down on 28, 24, 21 & 14mhz. The symptoms are when you go into RTTY and turn up the RF Power, around 50 watts on 14mhz and @ higher PO levels on the other bands, the spectrum display grows until it starts to generate "grass" around the center triangular display. There is also a "hum" in the speaker when this happens.

This is into a dummy load or the antenna. I switched coax, same problem. I switched antenna sockets, same problem.

The radio works fine on 50, 18, 10, 7, 3.5 & 1.8Mhz. You can crank the PO up to full with no "hum" or "grass" on the display.

I'd appreciate if anyone has had or knows someone that had the problem & has a fix, could you pls drop me an e-mail.

73's,
K7OCR

forrestw@gbis.com

W0LPQ
03-07-2007, 02:54 AM
Sounds like a BPF problem or loss of switching devices for the BPF. #

You might contact Adam, AB4OJ. #He is moderator of the 756 Pro III group on Yahoo.

http://www.ab4oj.com/

Bill, W0LPQ/9

n7ld
03-07-2007, 03:27 PM
Bill ... thanks to you it's fixed.

I gave the blow by blow to Adam VA7OJ/AB4OJ & in Adams response was "Can you check the radio with a different power supply?"

http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

It was the power supply. Something I changed a few wks ago, but just now noticed the issue.

Mucho thanks & thanks to Adam.


K7OCR http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

W0LPQ
03-07-2007, 03:45 PM
Good show OCR ... that is what Adam does best.

I use a Pro II/7000/TR-4C/SR-150 ...! But am slightly biased to the Pro..!

Bill, W0LPQ/9

W0BKR
03-08-2007, 04:16 PM
Hey, glad you got some help from a fellow amateur! That is what it's all about!

Quite knowledgeable folks on here....