Skip to main content

7O6T Jemen comming soon (QRM pileups expected.. / K3 on 70MHz

they start at 21:00 UTC 30 April

Today again there was ES on 70MHz  not here but west G was working to CT.  And I found I was not ready for it. Got a bad  audio report when calling USB very bad report.

Now after running WSPR mode on 70.091 since the end of January  many many WSPR reports are received and decoded using the Flex1500 and WSPR V2.21. I got it reasonable stable and the time-on counts is over 1200hours already.

Now the ES season is approaching but operating  CW or Phone is a headache.  The internal keyer is useless, the SDR time delay make it impossible to give code I could not send my own callsign I tried it impossible!  And in the past I have used keyers  that nobody could use. CQ-ing using my tones is way easier then  let the code pass the SDR processing...
In phone the output is too low few microwatts?  in digimode tune or CW  the level is normal about 0dBm.
The microphone gain must be set very low or the audio will be totally  distorted.  But even then the peaks  are too low to drive my XVTR that needs about 1mW  0dBm.
The output using the external mike must be way down 1mW level for unknown reason I could not find a good setting.

Tuning with mouse I never real got used to it, it is not easy to just swing over the band although there is a special tuning wheel for that i do not have it.  The complications setting audio VAC in combination with W7  is a puzzle. Once working don't touch anything! The regular need for a reset of Power SDR is getting on my nerves.
Not  being able to work split frequency with XVTR is bad.
An extra handicap on 70MHz  where some countries in EU have different band segments.
It is all too much a handicap in operation for me. I like fast CW and fast overs in phone.
Where are all the users of the Flex1500?  I never heard or worked a ham using a Flex1500?  are they all satisfied?  Am I doing  something wrong here? I only know Ross VK1UN  T51/ T61  he has one and experience same problems.
Al together it was a nice SDR experiment I like some things of SDR and it has the future but the 1500 badly needs improvements.

So why not then use the K3  and its KXV3  connections for that.

I still can use the external RX antenna for the K9AY lowband receive.
That is connected to RX-ANT in separate.
I did that and compliments to Elecraft  for the simple logic and good setup of XVTR use. 
Just CONFIG  set XV1  on =yes
XV1 RF  70   (70MHz   start of band
XV1 IF   28   (28MHz)
XV1 PWR L 1.47  ( 1.50 mW is max  to use the KXV3 XVTR out )
 XV1 OFS  -.20     ( my local oscillator needs correction)

connect the XVTR 28MHz  Rx/TX  to  KXV3 XVTR-out
connect T/R  cable RCA  to PTT-out   ( pull down to TX)

and that was it!   The Band switch now has an extra Band added
called XVTR 1   so tap up the band from 50MHz will go to 70MHz  now.
Split freq does work  of course  why shouldn't it?? 


Popular posts from this blog

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…

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 …

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