Dialing problem of FT900 HF transceiver

Asked By Zarah Mosley 10 points N/A Posted on - 01/14/2012

Hello!

I own an FT900 HF transceiver that works very well from the 14.50000 and higher dial readings; but the problem is that it shows no response when the dial reading is at 14.49999 or below. Given this situation, I was thinking that this may be caused by faulty VCO1 and VCO2; but why is it that both do not work? Is that possible? I can’t find a solution/answer for this. I hope you could help me. Thank you very much.

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Answered By Michelle Bang 55 points N/A #115953

Dialing problem of FT900 HF transceiver

There might be a problem with the VCO1 and VCO2 in this case but we can't be sure about that because it is working well at 14.5000. So first of all start all things from beginning. Connect the DC meter to TP1003. Tune the display to each adjusted frequency in the following ratio given in the table and then you should adjust the corresponding trimmer capacitor for 6V on the meter. Then return to the checking frequency and confirm the corresponding check voltage that should be more or less 0.5V. Repeat the same process for each type of frequency

Adjusted freq @ VCO#	Adj for 6V @TP1003	Checking Freq.	Checking Volts
30.0000VCO4	TC1005	21.50000	1.8
21.49999VCO3	TC1004	14.50000	1.8
14.49999VCO2	TC1003	7.50000	1.6
7.49999VCO1	TC1001	0.10000	1.7

Hope it helps

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• Posted on - 01/20/2012
• Question Category: Hardware Components