06-13-2022, 11:25 PM
I think you are better off with the switch. This way, you can leave the MP3 connection in. The only thing I would do differently is not have the 10K resistor. This would allow a true (ceramic) Phono connection (which can still use the 3.5mm jack using the correct adaptor) or other input that is lower than the headphone output. Ensure that there is still a cap somewhere in the circuit between this input and the 1st AF Amp grid.
If the dropoff does not coincide with switching bands on the Radio, it could be an issue with the 1st RF or the Convertor Tubes. 6SK7s and 6SA7s were common RF Amps and Convertors for shortwave radios up to about 18MHz, but i am sure that their performance falls off. If you hae a shortwave that works well on that band, try swapping the tubes between the 2 radios. This will also be a good test for your Sig Genny
Best Regards,
John MrFixr55
If the dropoff does not coincide with switching bands on the Radio, it could be an issue with the 1st RF or the Convertor Tubes. 6SK7s and 6SA7s were common RF Amps and Convertors for shortwave radios up to about 18MHz, but i am sure that their performance falls off. If you hae a shortwave that works well on that band, try swapping the tubes between the 2 radios. This will also be a good test for your Sig Genny
Best Regards,
John MrFixr55
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
Best Regards,
MrFixr55