Re: No Power


Many Thanks Ian.

You have help me to solve the problem. Firstly I have been pressing PTT and then keying up. When you described the changes I should expect and as I had no change just keying I checked the commercial keying lead and it had an OC earth connection. I had previously just checked the inner.

Repaired and it popped into life.

Power out is low but there are many suggestions for setting bias and many other ideas.

Getting 2 W on 80M and 40M but .5W on 15M

This is a fantastic piece of learning, even if mine was a basic one, relying on a commercial lead.

Thanks to all and now more trawling and reading so I can get it digital.

Peter Paul Fox G8HAV
Mid-Cheshire Amateur Radio Society
5 Llandovery Close
Cheshire CW7 1NA 

Group Controller
Dane Valley RAYNET 
Tel: 01606553401 (H)
Tel: 07919315547 (M)

From: <> on behalf of Ian Lee <kd8cec@...>
Sent: 12 June 2018 00:24:36
Subject: Re: [BITX20] No Power

Press CW Key and the screen (second line) should change as shown below.
(This is the same for stock firmware, CEC Firmware)
LSB A: 7.010.000     (receive)
    CW: 7.010.000     (when press cw key)
     TX: 7.010.000     (when press PTT)

If there is no change in the screen, check the CW Jack and CW Line. Especially, check the resistance part attached to CW Jack
If the screen changes as above, please check if you can hear the side tone and the relay sound from the speaker.

You can test it with the scope or spectrum analyzer as follows.
RX : 
  CLK0 : 11.9 to 12 MHz measurement
  CLK2 : It depends on your receive frequency and mode.
              if your mode is 'USB' and 
             44998500 + your Frequency = meaurement frequency
TX :
  CLK0 : 0 Hz (Sleep)
  CLK2 : TX Frequency +- (2000Hz because of applied side tone)


2018-06-12 4:09 GMT+09:00 G8HAV <g8hav@...>:
Thanks Allison and Lee.

There are no changes on the LCD screen. just TX and the frequency in use VFO A. CW is set to ST.

The CW-KCLK#2 R100, and it is not a clean waveform; Scope indicates about 100 mV average.

Hope this helps

Best 73
KD8CEC / Ph.D ian lee
kd8cec@... (my blog)

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