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Old 23rd Nov 2020, 10:24 pm   #33
Keith
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Join Date: Jan 2003
Location: Tewkesbury, Gloucestershire, UK.
Posts: 589
Default Re: Wireless Set 19 Mk3 transmit.

Hi again Carlos,

The HET TONE control only operates in CW mode receive. It is switched out in transmit so that the transmitted frequency is not affected. If you are getting a continuous tone in CW receive (even with no signal), this means that the twin-tee peak filter is oscillating. This may be due to component value drift and/or incorrect loading of the RX output (possibly wrong impedance headphones). This is quite a common problem. ISTR that there was a modification to provide an additional damping resistor somewhere in the harness to fix this in service.


The NET switch allows netting (zero beat) of the TX frequency exactly to the received signal in R/T mode - this does not involve the HET TONE control. You will probably have to reduce the RF gain control to hear the beat on a strong signal.


Hope this helps.
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