July 21 VUS contest

During the time i was qrv i experienced very low participation from DL. Activity from OK was quite good. Some nice AP scatter QSO arranged via ON4KST chat but also random QSO. The SDR really helps to find the people when turning the antenna. Average of 270km/QSO on 70cm and 220km/QSO on 23cm are quite ok for me for operating from home.

Saturday evening 70cm. Rig HiQSDR+Iceni Transverter, 50W, 15ele.
27 QSO 7300p, ODX S59DGO, 610km.

70cm 21/07 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer


Sunday afternoon 23cm during the last 2h of the contest.
Rig HiQSDR+MKU13G3, 100W, 36ele.
25 QSO 5500p, ODX S50G, 560km.

23cm 21/07 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

And i almost forgot: 1 QSO on 3cm with OK2A ;) Rig: FT790R2, Transverter, 10W, 40cm offset dish and W1GHZ feed.

DUR June 2021

17 QSO on 23cm and 2 on 10GHz. Quite good activity on 23cm due to ongoing Alpe-Adria Contest.

DUR 21/June 23cm result – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

2021 June NAC 70cm

Rig: HiQSDR, Iceni Transverter, 50W, HA8ET LNA, 15ele
Result: 13QSO, 5900p, ODX SM6VTZ 820km

I drilled some additional holes into the boom of an old 21 Tonna fragment in order to mount the mast clamp. Together with a 2nd segment this gave 15ele with some suboptimal clamp mounting close to one of the directors. But better than my 5ele lightweight i estimated. It turned out to be right.
Some of the OZ stations where easy to work. OZ1DLD/P even in SSB. Outstanding signal from SM7DTE. ODX was again SM7VTZ with a rather short AP reflection this time. But i was happy to work him with my 50W qrp signal. An average of 424km per QSO is surprisingly good.

15ele made of parts from 21ele tonna


my 70cm “transverter in a box” mess. But it does the job.

Jun21 NAC 70cm – (C) OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA) – created with DL4MFM log analyzer

IARU June contest 2021

Because of some Covid restrictions still in place in DL there was the decission to remove the nigh time from the contest period in Germany. For me this was a very unfortunate decission since this is usually the only time where i can operate without interruptions or other assignments.
In the afternoon there was quite some RS condition. I tried to find some QSO partner on 6cm but did not succeed. I heard DB0FGB (JO50), DB0NCO (JN59) and a OK station calling. The OK station did not come back to my call and i was not lucky in the ON4KST chat.
Videos of the beacons received:

Watch this video on YouTube.

Watch this video on YouTube.


Then i switched to 10GHz. Usually i am limited to direction south because of problems moving the dish through the upper roof window. This time i managed to put the little plastic dish outside to work some station to the north. At least DF0YY made it to the log this way.

Dish for 3cm on the roof top direction north-west


Jun21 3cm – (C) OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA) – created with DL4MFM log analyzer


Rig 3cm: FT-817, old transverter, 10W, 35cm dish with W1GHZ dualband horn
Result 3cm: 7QSO, 660p, ODX OK1FPR 200km

Later i tried 23cm. 10pm local time was already close. But i was not sure if i would be able to do some more QSO on sunday. So i decided to give some points to others outside DL at least and continued for a while. In the end i did not switch on on sunday again.

Jun21 – 23cm – (C) OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA) – created with DL4MFM log analyzer


Rig 23cm: HiQSDR, MKU13G3, 100W, 36ele
Result 23cm: 19QSO, 4600p, ODX HA5KDQ 550km

NAC2m June 21

Short participation in 2m NAC.
Rig: HiQSDR, ME2T, 200W PA, 4ele
A nice SSB QSO with SK7CY, ODX PA0O 540km.

June 21 NAC 2m – (C) OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), map created with DL4MFM log analyzer

DUR 21/05

2 of 3 hours from home. Quite good on 23cm. Some nice QSO on 9cm. Unfortunately no QSO on 6cm.

21/05 DUR 23cm Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer


21/05 DUR 9cm Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

March 21 IARU contest

Since there were still heavy covid restrictions and no chance to sleep somewhere we decided not to go to JO60OM for multi-Op. I was planning to be part time qrv from home in JO61UC. Since i completed my test-setup of the Iceni 70cm transverter i was able to operate 3 bands, 2m,70cm,23cm. More bands are not possible because the mast is too short and 13cm is not ready yet.
Despite i thought different my main operating time was saturday afternoon. I started with 70cm because i was curious for this band that i never operated from home before. It started very slow, almost nobody qrv in the beginning. During the contest some nice QSO came on top with S59P and S57M. Keep in mind that this is only 5ele and 50watts.

70cm March 21, OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM Log Analyzer


I later changed to 23cm and did some qso there. On 23cm it is a bit easier since i have 36ele and 100W. Many thanks to DL3IAS and DL3IAE for the ODX QSO via AS.

23cm March 21, OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM Log Analyzer


2m i started in the evening after the kids were sleeping. Unfortunately the conditions were very poor and i ended up with frustrating 20 QSO.

2m March 21, OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM Log Analyzer


Overall the result was a bit disappointing with the highlights of the 70/23 ODX QSO and the fact that the 70cm transverter was working fine.

Some more about SAW filtered LNA

The 1090MHz filters arrived and i measured this variant plus one without filter.

Closer to the filter the response looks quite ok:

LNA 1090MHz

Far away from the passband the supression degrades. Especially very high frequencies pass the filter quite well.

LNA 1090M span 3GHz

This is the assembly with 47pF capacitors and a 27nH coil for supply of the MMIC. Below 200MHz does not pass the capacitors well. There is even some remaining gain at 3.4GHz although its a 1.6mm thick FR4 PCB.

LNA without filter

LNA with SPF5043 and SAW filter

A while ago i tried the Eagle import capabilities of Kicad. I used a design of the baloon experimenteer “TT7” from Czech Republic and did some modifications to the layout. Since the LNA looked promising i sent the design for production and ordered some components. I had to replace some components for easier sourcing.
The MMIC i replaced with the compatible type SPF5043. Instead of the 3.3V regulator i used the variant with 5V output and up to 16V input. The options for the SAW filters are limited. The 70cm filters usually allow for the lower half of the band but the curve will degrade around 437MHz. A filter for 23cm and one for 13cm was availabe as well. The same for 1090MHz. Unfortunately none for 405nm was available. There is an option for phantom feed of the LNA as well as mounting an ESD diode. Unfortunately i did not care about the width of the RF traces. They are far to wide. Fortunately the trace in front of the MMIC is short.

SAW filtered LNA


For test i assembled one board for 70cm, 23cm and 13cm each.

LNA 70cm


As written above the 70cm SAW starts to attenuate a lot around 437MHz. There was a type with broader response but it is available nowhere.
The overall gain is about 18..19dB which is in line with MMIC and filter datasheet.

LNA 70cm wideband


Looking to the wideband response of the filter reveals that it looses its filter capabilities over 1200MHz.

LNA 23cm


The filter used for 23cm is a bit wide. It exceeds the amateur allocation a lot at the lower end. At the upper end 1296MHz is already at the edge. The maximum gain is around 1180MHz with 13dB. For 1296MHz it results in roughtly 8dB gain only.

LNA 23cm wideband


The filter capability is maintained over a broader range and de-rates at over 5GHz.

LNA 13cm


The filter for 13cm fits pretty well. Although the MMIC has even less gain the filter also has less attenuation than the 23cm type on 1296MHz. Therefore it also results in about 8db gain.

LNA 13cm wideband