Skip to main content


 3-1-2017 F6DHA met veel power en multipath traces
na 2 dagen  de eerste decode's op 144489 ( dial USB)
 2017-01-02 18:22  PA0O  144.490552  -11  -3  JO33hg  10  DK6UG  JN49cm  431  165

IC706  10W 144 
Daaronder Comtex  QJ1830SC lineare voeding
Fraai opgebouwd  30A 13.8V met 6x PIT3055  
  Opvallend stabiel 0-5A  geeft minder dan 10mV verval
haast beter dan een zware autoaccu.
Slim ontwerp rond een standaard LM324 opamp.
 Verlichte meters waarvan de A-Meter er plotseling mee ophield.
Werkt weer na reflow van de meter klemmen.  
De LM324 moest direct in het begin worden vervangen.  
Aan het ontwerp en uitvoering van deze voeding zal het niet gelegen hebben dat is top.
 Een 100R over de thermische schakelaar geplaatst zodat de ventilator altijd iets koelt.
Deze th-schakelaar  komt zonder 100R bypass al in met lage belasting.
Dat zou mooier kunnen met een traploze ventilator sturing.
Als verbeter puntje

 moet via het lange pad  om deze tijd  meetkundig  40032-17771 = 22261 km
dat lijkt me te veel maar het is minimaal 500-1000 km meer dan vanuit G  of  EI 
ipv  500 -1000 korter

 2017-01-03 07:36  PA0O  3.594147  -24  0  JO33hg  1  ZL1RS  RF64vs  17771  32 
 2017-01-03 07:48  PA0O  3.594147  -24  0  JO33hg  1  ZL1RS  RF64vs  17771  32


Popular posts from this blog

SPF5189z Low noise preamp 23cm

14-4-2018 updated

Above the low noise  preamp 50 - 4GHz    ebay  6€

Tested  2 small porto antennas
1 Baofeng UV antenna left   2nd best signal on PI2NOS
2 eBay DIAMONDSRH805S  wide band 144/432/1200  it works for its size as expected
3 piece of wire :   best signal in the setup...

Unit under test at workbench.
It was stable  50mA  at 5V   few days,  but sudden the current went up to 100mA
And i could  no longer adjust it with the negative bias Voltage.
The - Voltage went to zero and the SPF input port became low Z.
This SPF5189z was broken  no oscillations, no input overload just it broke while i was receiving the PI2NOS 430.125 using a small antenna at the workbench.

The specs of  SPF5189z  say it has an internal circuit  regulating the bias current.
Replaced . again   with an other of the 5 spare SPF i have.
The new one again could be adjusted at 50mA  5V 
The current raises to 150mA  when removing the  negative gate voltage.
Where is that internal bias circuit ?
I suspect  eBay …

2011-01-22 DIAMOND X30 2m 70cm 1m30 Colinear inside

Having relative poor signals on the local 70cm / 2m channels using this Diamond collinear 70/2 combi antenna at a height of 25m. I needed to investigate what could be wrong.
Measuring the cable only 3W is left for the antenna of the 10W 435MHz output from a IC451E
The cable is 30m type H100 Z50 10mm outside diameter it is semi air-spaced but has an impossible 4mm² solid CU inner conductor not much air left. I preferred the H43 Z75 cable having lower loss and mechanical better ratio in conductor size but it is no longer selling i think. This H43
3W should be enough for a comfortable noise free FM signal. But only 27km away at PA0A the signal is weak too weak something must be wrong? I made a simple reference dipole of 2x17cm CU wire.
With this dipole the signals where totally worse. So the Diamond does work?
I got curious to look inside. Maybe moisture penetration degraded the antenna.
This  antenna is rainwater close in its normal vertical mounting position. But take care if your mast can b…

Nice opening10m and 12m to S.A.

SFI  low 70 a 16 K3  still 10m opened up in afternoon to N-Italy EA5 F JN33
F/PD0OHW/M in JN33 decoded 150mW

VP8LP  12m    2-way with GP 7m ag swr 1:3

60m 5,362 open to ZL every? morning