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G8MNY > TECH 24.08.18 09:47l 100 Lines 5080 Bytes #999 (0) @ WW
BID : 35142_GB7CIP
Read: GUEST
Subj: My Home HF Set-up
Path: IW8PGT<IZ3LSV<IK6ZDE<VE2PKT<GB7CIP
Sent: 180824/0836Z @:GB7CIP.#32.GBR.EURO #:35142 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW
By G8MNY (Updated Jul 18)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
After several years of HF of improvements, I have ended up with this....
___
LS<ÄÄÄ´BHIÃ<DC ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ<20ft Noise Aerial
12cm ³DSPÃÄÄÄÄÄ¿ PTT ³ in front Garden
ÀÄÄÄÙ LS³ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ)Ä¿ÚÄPA FAN
______ ___³_ ³ _________ ³ ³³ _____ _______
Mic>´Auto ÃÄ´ICOM ÃÙ DC>´Noise ÃÙ ÀÁ´T500M³ ³PalstarÃÄ1kW PEP Dummy load
Ú´caller³ ³IC735ÃÄÄÄÄÄ´CancellerÃÄÄÄÄ´ HF ÃÄ´AT1500 ÃÄ>80/40/20/10 Dipoles
H/P³ÀÄÄÄÄÄÄÙ ³ RIG ÃÄÄÄ¿ ÀÄÄÄÄÄÄÄÄÄÙ ÚÄÄ´ PA ³ ³ ATU Æ())ÍÍÍÍÍÍ>160m Dipole
³ ÀÄÄÂÄÄÙ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÙ ÀÄÄÂÄÄÙ ÀÄÄÄÄÂÄÄÙ ÂÄ back Garden
³ DC³ ___ ALC _____ ³13.8v _³_ ³ RF
³ À´PSU³ ³SMPSUÃÙ //// ³Sniff
³ DC<Ä´20AÃÄ<M ³ 75A ÃÄ<M ³
³Y1 ÀÄÄÄÙ ÀÄÄÄÄÄÙ ³
_³___ Y2 ³ ÚÄÄÄÄÄÄÄ¿
³SCOPEÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ M<Ä´FiltersÃ<Mains
³_____ÃÄ<M ÀÄÄÄÄÄÄÄÙ
FEATURES
PSU Homemade Linear type, with 3A trip for low current leads, & mains filter.
SMPSU converted DEL Server one, with thick PA DC leads, & Ferrite rings.
BHI DSP LS gives 10-20dB of noise reduction, used with a large LS.
Noise Canceller JPS ANC-4 with aerial, gives >15dB of QRM nulling on 1 source.
IC735 sometimes used with very effective tuneable Noise Blanker or Attenuator.
Auto caller Home-made CQ repeating & off air record & playback.
IC735 used with it's very effective AF processor (10dB clipper) & standard Mic.
T500M PA draws 75A @ 13.8V, so use SMPSU or float a car batts with thick leads.
My T500A ALC ensures the Amp can't be over driven even on 11V DC or a bad SWR.
Palstar AT1500CV ATU, cross needed power, handles high SWRs & can be balanced.
Dummy load with PEP meter gives accurate PEP power measurments (scope option).
Scope for monitoring Tx envelope & Rx Noise (timebase locked to mains).
Mains filters both include earth chokes.
ON AIR
I often get comments on how good the AF is (especially under noisy band
conditions), it is just a well set up standard AF clipper (compressor) in the
IC735 with it's toppy AF (do not clip bassy AF!) But it does not suit all ears
& strong QSOs, I turn the compresser off. And I always use close up mic, to
reduced background noise & room echo, & keep the ALC drive level correct.
The PA helps a lot, & when I go back to QRP stations M6s etc, & run their QRP,
they often can't hear me, or would not have called me with a weak QRP signal.
I have had very complementary reports on how clean (narrow) the QRO signal is.
E.g. "-35dB down on adjacent ch" & "You are much stronger than me at remote SDR
Rx site & also narrower!" So the old IC735 rig with its comms quality audio,
fixed narrow Tx IF, & older 1977 Commercial PA with high NFB, & my ALC are
keeping the Tx signal all very clean.
My Autocaller CQ, keeps the channel busy, while I catch up with paper log, or
get the perfect SWR etc. & then I get called. But it is a bit noisy on record
especially into the clipper. But it does make for lazy operating with less
scanning. I do use 2nd VFO for that & go back to my CQ VFO.
The 3 noise systems I use, the rig's tuneable Noise Blanker, BHI DSP LS, & JPS
Noise Canceller, all complement each other very well, as they work differently.
Sometimes all 3 are needed to get a usable band here in RF noisy Croydon. With
the JPS ANC-4, do not Rx too much Tx power on the noise aerial, as it can be
damaged with nearby QRO! Using seperated aerials as I do, stops this, & also
helps get deep nulls while leaving Rx signals, with same location aerials you
tend to null out all signals at once!
Scope timebase is locked to mains, & both beams are added to give just 1 line.
Rx AF can help adjust the Noise Canceller & rig Noise Blanker threshold, as you
can see the offending neighbours SMPSUs, & null out one pair of 100Hz noises,
but not if 2 or more appear on another mains phase. Not mains locked QRM from
TV/PC screens, polling data can be seen, & other non ham things like over the
horizon radar "Wood Pecker" or "QRO 50Hz FM sweep jammers" are easily identifed
too.
The Tx envelope display shows up the peak with or without compression, all
nicely rounded peaks under ALC power control, with no hard clipped flat tops.
See all these related TECH buls....
"Autocaller with old Maplin kit"
"High AMP Crowbar Protected PSU"
"DEL 7000815 SMPSU 12V 75A Mods"
"T500 M 12V 500W HF Linear"
"Variable Speed Thermal Fan"
"BHI Noise Eliminating DSP LS"
"IC 735 No RF Output Fault"
"Palstar AT1500CV ATU"
"QRO 1kW HF Metered Dummy Load"
"A Nest of Dipoles for HF"
"Mains Plugtop Filter Adapter"
"Oscilloscopes"
"AF 2 Tone Test Osc Design"
"QRO v QRP".
Why Don't U send an interesting bul?
73 de John G8MNY @ GB7CIP
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