Search found 56 matches

by G4AON
Thu Feb 07, 2019 11:29 am
Forum: MMDVM_HS Hat(s)
Topic: Low RF output
Replies: 5
Views: 6529

Re: Low RF output

Problem sorted... This Chinese copy MMDVM board had incorrect parts fitted in the "T" network filter. I removed the components (C27, C28, L1, L2 and C1). Then bridged directly from the junction of C4/C5 to the SMA socket side of C27. While it means the board is running without filtering an...
by G4AON
Fri Feb 01, 2019 6:45 pm
Forum: MMDVM_HS Hat(s)
Topic: Low RF output
Replies: 5
Views: 6529

Re: Low RF output

Thanks Brian I’ll check on Monday, but I think it’s the correct parameter. I also have a Pi 3/DVAP. I’ll check that and see what effect the RF parameter has. It would be useful if someone with an RF millivolt meter or spectrum analyser and an MMDVM would check theirs. Maybe many have flea power leve...
by G4AON
Thu Jan 31, 2019 5:19 pm
Forum: MMDVM_HS Hat(s)
Topic: Low RF output
Replies: 5
Views: 6529

Re: Low RF output

Thanks Brian

This one has an LCD display that makes access to the L/C output parts awkward.

Should the Pi-Star config alter the RF O/O on the MMDVM boards? My changes had no effect...

73 Dave
by G4AON
Thu Jan 31, 2019 4:27 pm
Forum: MMDVM_HS Hat(s)
Topic: Low RF output
Replies: 5
Views: 6529

Low RF output

Checking the output power on my Spectrum Analyser, it seems very low at -35dBm. It’s one of the Chinese eBay ones and is set for 434.800 I removed the capacitor to the on-board antenna without any noticeable difference. Altering the RF output under Pi-Star Config makes no difference either. While th...
by G4AON
Fri Aug 24, 2018 5:13 pm
Forum: DVAP Dongle
Topic: 2m DVAP Transmit Lockup Bug
Replies: 5
Views: 12806

Re: 2m DVAP Transmit Lockup Bug

I too use a 2m DVAP, but as far as I know have never experienced any lockup, either with Pi-Star or any other Raspberry Pi software. My DVAP is mounted directly on my R/Pi, uses the small stubby antenna, and is set to -10dBm output. I use WiFi and only have the power cable and a short (6") USB ...
by G4AON
Wed Apr 25, 2018 1:35 pm
Forum: DVAP Dongle
Topic: A tip for new Pi-Star users
Replies: 3
Views: 11180

A tip for new Pi-Star users

The Windows software for the DVAP dongle, and some Raspberry Pi images, allow you to access the D-Star network with a radio on simplex set to the Dongle frequency and D-Star, ie without being specifically programmed. This doesn't work with Pi-Star. The Pi-Star image will not work unless the radio is...