I spotted that one as it popped up after the first video Paul. Noise attenuation is really significant. I must go and check my ferrites and make a couple of those gizmos. In the video, if you look aro

I have a very large selection of ferrite rings etc many from scrap equipments. Is there an easy way to identify the material in such things? A simple RF test maybe? Allan G3PIY

Lots of your compatriots are into the WS19 Alan because many were built in the US and Canada. Of course it doesn’t have a USB lead but it has loads of knobs on the front and great for pirating in the

Sorry, my computer has decided to send WS19 emails to the SDR forum Apologies Allan G3PIY

OK Jacques I made some notes in my reply to Chris. The 5 watt dummy load was only for low power checks and I do have proper high power varieties. The 807 coil doesn’t look like it’s High Q. Maybe I sh

Sorry folks.. my mistake.. I posted on the wrong forum. Clearly it's me that needs looking at not just my WS19 Allan G3PIY

My rebuilt WS19 Mk3 is working OK on receive. I decided to check it in transmit, but rather than connect the full 550 volts or so to HT2 I connected a variable HT supply. This is calibrated from 0 to

I was thinking I may be celebrating too soon Dave. We had 3 or 4 power cuts last night and our next door neighbour is away and I can't help thinking something in his house turned itself off, because w

Yes Dave… case closed. Funny thing though. I've had several broad bands of infuriating chopper noise spread across the range 200 to 500KHz. This resulted in motor bike noises on everything except Radi

Hi Dave I must admit that the 16KHz signals do not worry me but HF interference does. This morning with wind and rain and no direct sunlight the 16KHz signals are ticking away at around 300mS interval

Lee I had a cry for help from an Isle of Wight ferry company. It seems a commercial appliance bought cheaply because it wasn't spec'd for the marine environment was wiping out one of their VHF channel

OK for valves but maybe not transistors? Allan From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of jose maria trueba Sent: 08 February 2020 11:33 To: main@sdr-radio.groups.io

If I place a +/-200Hz AM window over the strongest signals which are 100Hz apart I can hear a 100Hz hum. No trace of anything on an individual signal, however (but could it be phase modulation?). When

Dave I would need to walk around the village to see if there are any solar panels other than the group I know which faces SE. It was blue sky weather here when I monitored the 16KHz signals at 16:00.

What about TVS bi-directional diodes. These are rated at hundreds or even KWatts and can have pretty low capacitances It will be a trade off... power rating versus capacitance and clamping voltage Typ

I tried NFM, AM and CW but no modulation is present. They seem to be unmodulated crystal controlled carriers. As I decreased the waterfall speed the traces got narrower and cleaner as you would expect

Dave This morning I was experimenting with different power supplies for my Andrus SDR. Two different USB PSUs from Amazon gave an unacceptable buzzing noise about every 30KHz across LF and MF so I rev

Hi Dave My other similar groups are centred on 70.23 and 73.56KHz, but these are not crystal controlled, the former being weaker and the latter sounding rough with possible a 100Hz hum. The 16KHz sign

Dave Looking up EMI from solar panels yields no precise details, mainly discussing HF QRM with one comment re Radio 4 long wave. By switching the waterfall view to give the slowest, higher definition,

The signals present exactly the same when a 50 ohm terminator is fitted at the aerial socket so must be from inside the SDR. As I watched the traces, all started communicating, apparently with some so