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QRM QRM QRM in a would be low noise QTH

28.074MHz  FT8 band  with S5 noise

today ALL BANDS  are polluted with QRM  0 to 1300MHz

S5 Noise 28MHz S7 21 MHZ
whole spectrum is  30dB and higher noise plus carriers  digital smog
 50MHz  30dB noise from the Solar EDGE broadband transmitter

AT  Dutch Telecom say it is within the legal limits
They could not even detect it on their mobile equipment
It is legal to make RF smog as long as the GSM traffic and other services  is just good enough.

23cm 1.3GHz   never ending s7 QRM cracking from direction S-W
28 MHz complete covered with S5 sm noise day and night
50MHz  noise raise to 30dB  in the direction of SOLAR EDGE  system at 50m

from almost 0 to  at least 150 MHz  every 200kHz  a group off digi trash carriers

I have to investigate this myself
The  Agentschap Telecom can only detect radio interference that exceed levels of 50dB
on normal radio HAM receivers 

5362kHz Stanag  signal from Denmark 9+60bd !!

i am not the only HAM negative surprised by this DX blocking 9+60  exactly at the wrong spot
where the 60m band seem to have plenty of room for such transmissions it has to be exactly on top of the ZL channel


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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