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Small PA  2 x MRF186 eBay 100W VHF PA kit   in operation
using K3  144XVTR   5/7 ele  4/2m  dua band antenna
Arduino SWR alarm /Power display modified ON7EQ

Call signWorkedDate/TimeBandModeFreqQSL
DetailsPA0OKB2FCV2019-04-02 05:33:15160MFT81.84190UNITED STATES OF AMERICA
DetailsPA0OK4SE2019-04-02 05:21:30160MFT81.84074UNITED STATES OF AMERICA
DetailsPA0OW0UVC2019-04-02 05:20:15160MFT81.84074
DetailsPA0ONE0DX2019-04-02 05:13:00160MFT81.84074
DetailsPA0OKI5BLU2019-04-02 04:57:15160MFT81.84098UNITED STATES OF AMERICA
DetailsPA0ONC6K2019-04-02 04:55:30160MFT81.84098UNITED STATES OF AMERICA
DetailsPA0OV31VP2019-04-02 04:50:00160MFT81.84098
DetailsPA0OPE1NPS2019-04-01 21:26:152MFT8144.17487NETHERLANDS
DetailsPA0ODD1UN2019-04-01 21:18:152MFT8144.17487
DetailsPA0ODM5TI2019-04-01 21:09:002MFT8144.17474
DetailsPA0ODL1OBF2019-04-01 20:59:452MFT8144.17474
DetailsPA0ODL4EAX2019-04-01 20:25:452MFT8144.17474
DetailsPA0OG3YDY2019-04-01 20:17:152MFT8144.17474
DetailsPA0OG8JLY2019-04-01 20:12:152MFT8144.17466
DetailsPA0OM0BEW2019-04-01 20:09:302MFT8144.17466
DetailsPA0OPD1JFB2019-04-01 20:02:452MFT8144.17466
DetailsPA0ODK3DUA2019-04-01 19:48:002MFT8144.17466
DetailsPA0OPD0FGQ2019-04-01 19:44:302MFT8144.17466
DetailsPA0OF8DFO2019-04-01 19:41:152MFT8144.17466
DetailsPA0ODK9CK2019-04-01 19:32:152MFT8144.17469
DetailsPA0OM0JDK2019-04-01 10:24:002MFT8144.17484
DetailsPA0OM0JDK2019-04-01 10:18:302MFT8144.17484
DetailsPA0OXR0ZRC2019-03-31 22:57:4530MFT810.13160
DetailsPA0OGW1YQM2019-03-31 19:50:002MFT8144.17469WALES
DetailsPA0OG8GXP2019-03-31 18:13:152MFT8144.17469

Early butterfly
No RFI issues using 1nF feed-trough and Ferrite clamps to the Arduino  


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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