I realise that GPIO pin 40 goes high on Tx. CQ-TV 271 p.12 states that the the pin only goes high once the SDR calibration pulse has completed. I guess this is to protect PAs from the spike. (I feel sure I have read somewhere that the delay is 100mS). However, it would be nice to switch Tx/Rx relays before the PA is activated by pin 40. I wonder what the preferred solution is? - perhaps activate the Tx/Rx relay directly from pin 40 and delay the PA by a few more mS?
Incidentally, is pin 40 similarly delayed in Langstone mode?
73, Russ.
Tx switching on PD4 & Langstone
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Re: Tx switching on PD4 & Langstone
I think I wondered this a while back Russ, there is a 100mSec delay in both PD4 and Langstone before any RF is emitted AFTER tx has appeared. Its all I use for sequencing......
Gareth
Gareth
Re: Tx switching on PD4 & Langstone
I have an 8 way output switch where Atv at 2.4GHz comes out of port 5 - a Portsdown setting. In Langstone mode it was out putting 2.4GHz FM to port 6. I hastily restored the missing connections . Hopefully G4EML will appear and answer the original question
73
David M0YDH
73
David M0YDH
Re: Tx switching on PD4 & Langstone
As Gareth says, Langstone has a short delay between the TX pin being set and the RF output.
Band selection is controlled by the Langstone 'Tx band bits' and 'Rx band bits' settings. These are independent of the Portsdown setting.
Colin G4EML
Band selection is controlled by the Langstone 'Tx band bits' and 'Rx band bits' settings. These are independent of the Portsdown setting.
Colin G4EML
Re: Tx switching on PD4 & Langstone
Many thanks to all for your helpful replies.
73, Russ.
73, Russ.