https://ei7gl.blogspot.com/2021/05/3000km-opening-on-144-mhz-between.html
screenshot gets blurred when placed here
3254km !! my best DX ever heard at 144MHz but the opening was to short to complete the reports
a once in a livetime experience ... today all band quiet again.
First there was also very special TA1BM in Istanbul km40lx 2154km the 2nd TA at 144MHz
The first ever worked TA at 144MHz here was in 2017 USB TA1D/3 calling cq Kadri from KM39BP West Turkye coast al long ES opening
Jan 4X/OM2IB was running 150W like me and e 2.2 wave long yagi here i have the 12ele M2 about 2wl also nothing special no EME power... with the vintage BRAUN SE400
144 ES
20210525 0807 144174.6 FT8 PA0O -05 LZ5GM +00 KN32
20210525 0821 144174.6 FT8 PA0O -09 TA1BM -17 KN40
20210525 1025 144174.6 FT8 PA0O -20 4X/OM2IB -16 KM72JC niet compleet
20210525 1037 144174.6 FT8 PA0O -14 E77T -17 JN94
20210525 1039 144174.6 FT8 PA0O +17 YU7ON -02 KN04
20210525 1045 144305.0 FT8 PA0O 55 LZ1JH 59 KN12pq
20210525 1053 144174.6 FT8 PA0O +12 YU7KB +13 KN04
20210525 1204 144176.3 FT8 PA0O -03 YO5OMT +04 KN16
20210525 1211 144176.3 FT8 PA0O -20 YO6DBA -22 kN36
VHF DESIGN LNA 2M QRO experience
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| ATF53189 removed here. The small white relais are extra separators a 3 stage band filter, 12V supply direct at the feed-trough or over the coax as i did. It draws 0.4A |
Since the VHF mast preamp was damaged by statics.
I am using again my very old SE400 for 144MHz. Its receiver is nice quiet and sensitive.
No computer connection but PTT is operated by PC for FT8 mode. The frequency in N1MM is entered manually for logging better then logging on paper anyway.
In the constant bad weather we suffer this "summer" the preamp died rather quick.
Though nice well build in a solid aluminium milled case. In my opinion it needs some improvements.
As it is, it is unsuitable for outside use in the mast where it should be.
To make it weather proof I applied Tectyl spray at the N-connector flanges with plastic tops over it of course, and sprayed the case and some inside parts. Vaseline vet for sealing the top plate.
No mast clamp is provided. There are a few M3 blind threat holes that might be used for a DIY mast-clamp. I just used some binding wire.
There is no ESD protection.
The ATF53189 was damaged soon by statics ,the M2 12 ele has floating driven elements.
Should have placed GBLC03C ESD protection when it was on my work bench.
3V static protectors known from the Flex1500
I did insert 10R resistors in series with the diodes parallel over the 4 relais coils
to minimise relay fall off time hoped to solve an occasional T/R fault with the IC706 but that did not help , sure the relay fall off time decreased bit and the RX to TX switching should became a tiny bit faster though i did not measure it. General i insert a small 10R in series with the diode over relais if fast switching is important.
The preamp is powered over the coax cable 12V / abt 0.4A that is sequenced switched in the PA ,timed by the K3 PTT with build in 144m transverter. The K3 PTT to TX delay is 8ms default.
This way the preamp can handle full QSK.
My 200W max PA has fast relais and SWR protection switches the PA off at SWR above 3 . This happens if the preamp relais are not closed at TX time so if the switching timing is incorrect i will see the PA ANT fault immediate.
This happens with older rigs like the SE400 and also with the IC706 in lesser form.
VHF design did not offer me to send a spare ATF they have non in stock i guess.
The ATF53189 production is stopped.
I ordered 5 for 6$ at eBay , delivery estimated begin Juli ...
So i would rather recommend the more priceley SSB Electronic mast pre-amps they are ESD and weather protected. They come with an other prize tag dough.
They have RF VOX working simultane with the 12V sequenzer this also protects against unwanted RF power into the output by faulty operation.
The VHF design does not have an RF driven switching circuit.
I will repair the VHF Design and apply ESD protection
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| With all FT8 I did not forgot the old A1A Morse code.. |
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