DUR September 2018

DH5YM – DUR1809

Part time qrv from new QTH. Good takeoff direction south and nord. Only working direction south with very limited setup.
23cm 15W 14ele
13cm 1W ringfeed

Locator:: JO61UC
Band QSOs Points average
1,3 GHz 8 318 39.8
2,3 GHz 6 203 33.8

Band 1,3 GHz

Polar map for 1,3 GHz

20180916 SSB 09.11 DG0LFF 59 001 59 009 JO61VC 5 DH5YM
20180916 CW 09.19 OK1FJZ 599 002 559 011 JO60WD 107 DH5YM
20180916 SSB 09.23 DG5VL 55 003 45 010 JO61WA 14 DH5YM
20180916 SSB 09.24 OK1IEI 55 004 59 007 JO70EC 120 DH5YM
20180916 SSB 09.27 DH1DM 59 005 59 008 JO61TB 7 DH5YM
20180916 SSB 09.30 DG2DWL 59 006 59 025 JO60VR 42 DH5YM
20180916 FM 09.56 DG4VL 59 007 59 004 JO60VX 15 DH5YM
20180916 FM 10.27 DG1VT 59 008 59 001 JO61UC 0 DH5YM


Band 2,3 GHz

Polar map for 2,3 GHz

20180916 SSB 09.32 DO5UH 59 001 55 009 JO60ST 34 DH5YM
20180916 SSB 09.33 DG2DWL 59 002 59 012 JO60VR 42 DH5YM
20180916 SSB 09.35 DO1UZ/P 55 003 55 007 JO60RP 53 DH5YM
20180916 SSB 09.36 DL9NCI/P 55 004 55 007 JO60RP 53 DH5YM
20180916 SSB 09.58 DG4VL 59 005 59 002 JO60VX 15 DH5YM
20180916 FM 10.29 DG1VT 59 006 59 001 JO61UC 0 DH5YM

Some more sporadic E on 4m

Recent days showed some more sporadic E conditions. I worked EA and LZ. Monday evening i went away from the PC and when i returned i saw a CQ from 9K2YM. Unfortunately it was too late. Later on i also catched a CQ from S01WS. PSKReporter showed some really interesting spots by DK2EA. He received stations from the Carribean sea and others received transmissions from Japan and eastern China.

CQ of 9K2YM

4m ES condition on July22 2018.

BTW: the very nice and useful DXMaps page has changed to openstreetmap. Now its possible to show screenshots which was not possible because of license restrictions before. Thank you very much!

MSK144 QRP and ES0UG (/8)

This week some people from here work from Estonia under the call ES0UG (and ES0UG/8). Since there are no good ES conditions currently we tried MSK144 meteor scatter. I did not think there will be a lot success since i can only run 25W ERP. But finally i god some of their CQ.

ES0UG/8 calling CQ in MSK144 from KO18

During my lunch break i did not have success. In the evening we tried again and were able to complete the QSO to KO18 field within about 1.5h.

Since yesterday evening the crew is qrv from the next island in KO19. We tried again in MSK144 and this time we had bursts rather early. It still took more than an hour to complete the QSO and this time i have a nice screenshot.

ES0UG in KO19

Since i did not expect that it will work at all i am quite happy with my first two QSO via MS. I also got some spots from G3SHK. Many thanks!

Another great ES opening

This evening great ES opening to EI and G. And a surprise in between with S01WS.

It started in CW with EI4DQ in IO51WU and then i worked:

In the screenshots 23cm is displayed as QRG. This is because i use a wrong transverter setting in my SDR software which is taken over by WSJT via hamlib.

finally worked S01WS

big signals on 4m

4m ES opening June 1st 2018

This evening pretty good ES opening into several area of Europe. Also the 4m band was in quite interesting condition.
I worked some EA station + OH + SP all in FT8. Seems most of the stations are in this mode now.
Signal were pretty amazing strong. Also heard G and several times the OY6BEC beacon in IP62 as well as a LA beacon.




9cm DB6NT kit

Now i started soldering the 9cm transverter kit that was in the shelf since years. The filter caps look already a bit oxidated. But soldering still worked fine. The new 9cm will get into a box together with 13cm at some time.

9cm DB6NT MK2 transverter partly assembled


9cm transverter

G4DDK Iceni 70cm transverter

I assembled the Iceni 70cm transverter kit from G4DDK. Instead of the ADE-13 i used a ADE-751MH+. Sam was so kind and sponsored one of his mixer samples he used for testing. Unfortunately the manufacturer of the mixers uses different pinouts for almost every type. In this case i had to swap RF and IP ports. The good one: It is not difficult with the layout. In the picture you can see the short semirigid.

G4DDK Iceni transverter for 70cm

The next picture shows some IM3 measurement for the RX part of the transverter. The estimated input IM3 point is around 0dBm now (21dB gain).
The P1dB is about -9dBm (2x -12dBm).

Iceni ADE-751 IM3

I also checked the output signal. The 2nd harmonic is about 53dB below wanted signal and the LO suppression is about 58dB. So some extra filter might be required to the comply with regulations.
Overall i am very satisfied with this transverter block. With the alternative mixer the performance is even better than it was before.
Next i need to add a amplifier and other unimportant things like sequencer, RX/TX-switch, chassis and so on ;)

6cm PA chain

For my 6cm transverter i bought a 10W DL2AM PA years ago. Because it needs about 1W drive i combine it with the WLAN PA from here
6cm PA chain
The complete chain now has about 39dB gain and a P1dB of about 40dBm. So its working fine.

6cm PA chain output power

The current consumption for the both PA separately (orange driver current in mA, blue PA current in A).

6cm PA current consumption

A small VHF/UHF driver

I was searching for a small driver for 2m in order to have enough power for my microwave transverters. I usually drive them with about 500mW. Since i have a transverter block with about 0dBm output it needs some gain. Again i found something from China. The advertisement told something about 1.5W, the pictures showed a PCB with a print 35dB/3.2W. However, i thought it could be good enough to get 0.5W out of it.

A small VHF/UHF amplifier

When the device arrived i noticed that the manufacturer milled the top of the two amplifier IC. Very funny that the guys there try to save their designs from unwanted copy ;)
At the input there is a 6dB attenuation pad which are followed by two amplifier stages of unknown type. The first stage is supplied via a 5V regulator, the second one is connected to the supply input directly. I used 12V to do some measurements.
The first action was to know the gain of the circuit. I wanted to see if it is really working from 1 to 700MHz.
In the picture you see the little noisy measurement. The drive from the analyzer was set very low.

Gain of small VHF/UHF PA

From the gain curve it can be seen that the device is probably not working that well at the lowest end of the shortwave. But at least from 30MHz on it should be usable. Towards upper frequencies the gain is decreasing a lot but still 27dB at 700MHz. For the 2m band roughly 43dB gain is achieved and about 33dB in the 70cm band.
Finally i wanted to know which output power can be achieved in the amateur radio bands.

VHF/UHF PA output power

At about 1W output the output always gets compressed. You might add about 0.4dB on 70cm and 0.3dB on 2m to my measurements since the graph does not include the attenuation of the output cable. For me it means that the amplifier should work well for my purpose.

A simple 9cm monitoring receiver

Just for fun i tried to collect some components from the shelf and plugged together a simple monitoring receiver for 9cm.
I have a DF9NP PLL OCXO for 2592.2MHz and a pipe-cap filter tuned to 3400MHz. From China i ordered a wideband LNA some month ago. It has about 15dB gain on 9cm. The mixer is a ZEM-4300+ (+7dBm LO). The setup results in a IF of 807.8MHz which is received with an RTLSDR and the very nice GQRX software.
With a short wire attached to the input of the LNA i was able to receive the local 9cm beacon DM0TUD.

9cm monitor hardware

GQRX receiving DM0TUD 9cm beacon