On Tuesday, September 26, 2017 at 5:38:30 AM UTC+10, JS wrote:
On Monday, September 25, 2017 at 11:34:15 AM UTC-7, wrote:
Hi MN, I cant seem to find the pdf file you specified it took me directly to there tech notes section for the gliders. And they may have renamed/numbered I found nothing with 1997 or 20 on it.

And no I havent added anything new. I will try and turn my phone off next time it happens as that was the only thing I didnt try.

The old FSG71M is particularly bad at rejecting noise from other instruments.
I'm having similar issues with a 71M and LX V3 vario.
A current radio would fix it.
Jim

As Gianni commented, breaking squelch as described is very likely to be noise issuing from another device. (FLARM devices typically take up to 15 mins for first GPS initialization, 1 to 5 mins to locate satellites and update microSD card).

If you wind your squelch up to reject the initial interference then the radio will obviously then permanently reject all weaker transmissions as well.

Short term, it might be better to switch on early and wind speaker volume down initially.
Long term, you need to determine if the Dittle radio's squelch setting has drifted or some device is radiating interference.

Often each device is radiating a bit of interference, some more than others.. When it finally gets annoying / breaks squelch it is hard to determine which one is causing the most interference.
I have found that holding a hand-held aviation band radio (with squelch off / set very lightly) next to the instruments / wiring / microphone stalk is quite revealing. Often interference varies between radio channels. (Does the same squelch problem happen if you change radio frequencies?).

I have had success reducing squelch breakthrough from instruments using the following methods - Tightening screw terminals, cleaning / reseating connectors and fuseholders, reseating radio in cradle, replacing dodgy power switches, replacing end of life batteries, routing radio wiring away from nav wiring, ensuring the radio is on its own fuse and not sharing with nav gear, ensure radio and nav ground/negative wiring is really good, clipping ferrite noise suppressors onto suspect cables. (The clip-on ferrite noise suppressors are remarkably good, especially if you have enough wire to get 2 or 3 turns of wire through them). Be VERY careful if unplugging cables, it is very, very easy to let the smoke out if you plug them back in incorrectly.

Display panels, powerbanks and 12 to 5v converters are frequently very noisy.
Panel mount USB cables and microSD card sockets sometimes cause problems, try removing the cable / card if not vital.

Good luck, radio interference is a hard one, it often gets worse every time we introduce more distractions into our cockpit. As Jim suggests, modern radios have been designed to reject noise from modern instruments, older radios may benefit from having ferrite suppressors clipped onto the radio and nav gear leads.
Max