VLF/LF/HF Active Vertical !


WQ2H <wq2h@...>
 

23 Jun 2019 - 1802z - Greetings from the Granite State (New Hampshire) !

Installed the active vertical just in time to Rx the ARRL Field Day message from K6KPH in California (~4268 km) on 20m. Photo below. It's about 45' up now, and I have plenty of capacity to put a non-conductive mounting-piece in line if necessary. Installation was a snap - and noise levels appear much lower than my top-hat vertical for 2200m. (I call that the "noise magnet") Looking forward to listening for a few weeks on the low bands to see what comes along. I will share results if there is interest.

Thanks to Chris and everyone at CCW for their help on this.

73
Jim, WQ2H / WK2XAH



Chris Moulding
 

Hi Jim,

Thanks for the feedback and the photo, good to hear that it's working well for you.

I'll be interested to hear a report on how it works with 2200m (136 kHz) reception.

Regards,

Chris, G4HYG


WQ2H <wq2h@...>
 

Just an update:

Using this CCW antenna I (as WK2XAH) snagged a personal best of 3594 km 4-FSK (WSPR2) Rx from WH2XND on 137.5 kHz. Plenty of good activity on 474 also (up to about 800 km), but this was a real surprise. Also spent a few hours on a Sunday morning on NDBs - picked up about 30 new ones mostly from the Canadian Maritimes and northern Quebec. Good stuff !

73
Jim, WQ2H / WK2XAH







Chris Moulding
 

Thanks for the report on what you are hearing.

I've set up one of the VLF/LF/HF Active antennas at the workshop feeding one of the prototype Sentinel 4 receivers through a 150 kHz low pass filter to remove the LW and MW broadcast stations.

Best so far was hearing WSPR transmissions on 137.5 kHz from stations in Germany and Spain. The only problem was that the 4G modem we use in the workshop for internet access fell over that night so the spots from G4HYG/RX2 didn't get to the WSPRnet database.

I'm rather surprised how far 1W effective radiated power at 137.5 kHz can get.

Regards,

Chris


WQ2H <wq2h@...>
 

Chris, from my understanding, 1W EIRP on 137 is gargantuan.

Using the VK1SV calculator - the Hafler P3000 at 400W TOP is <500mW EIRP after going through the variometer. That places the voltage ~17kV.

Nice thing about that is that the corona arcs self-prune the adjacent foliage. LOL!

Antenna work here is ongoing - but as you would expect, the increments of progress are small. I'll be back on Tx in a few weeks.

73
Jim, WQ2H / WK2XAH


WQ2H <wq2h@...>
 

Just another update on the 630m side (from FN32vx).

Last night was the first night I monitored WSPR2 and JT9-1 with the CCW on 630. Extraordinary activity here on JT9-1 and -2, with several stations coming in at -10 dB from well over 1000 km away. Puzzling because we did have heavy rain and thunderstorms around us last night. For a while there I thought I was watching FT8 on 20m !

In the next few weeks I should have my 630 Tx capabilities up and on the air (thanks in part to K5DNL). I will advise of any QSO's I can muster.

Chris - great WSPR2 spots on 137, I see you have several at over 1000 km. I know it's a stretch - but I will advise once the 137 beacon is back on the air.

73
Jim, WQ2H / WK2XAH


Chris Moulding
 

Having the Sentinel 4 receiver in the workshop running WSPR 24/7 is proving very useful.

I did some listening on 137 kHz with the VLF/LF/HF Vertical with good results.

Over the last few days I've run tests with the WSJT-X program using band hopping from 160m to 10m to compare the VLF/LF/HF Vertical with a new revised version of the Broadband Active antenna I'm working on using a new grade of ferrite to isolate the antenna from the feeder.

Previously the performance of the Broadband Active antenna wasn't quite as good on HF as the other antennas we make but with the revised design it equals the VLF/LF/HF Vertical on 160m and above. This was proved by listening to the WSPR transmissions.

This evening I'll set it listening on 474 kHz with the VLF/LF/HF Vertical. I've never listened on that band so it will be interesting to compare with 137 kHz and the other HF bands.

Regards,

Chris