2023 June UHF/SHF Contest from JO60OM

Our local club DARC chapter S07 participates in the DARC Club competition. See our results page here (external).
Because of the UHF/SHF contest and the CW Fieldday both contributing to the Club competition we went to our portable QTH in JO60OM. There is a great mix of high altitude and very nice accomodation. Find some report of DL6JZ here.
Because of some family struggle i went to my parents home already friday evening. From there its only a half hour trip to Hirtstein. We met in JO60OM around noon and started to put the equipment. This time i took my 1.5m dish for 23cm and the 1m dish was planned for 13cm. Fred also brought his 6cm and 3cm systems.
The 23cm was my favourite configuration with 2x 100W (one for front system and one for the backside), the 23cm transverter with 10m IF and my HiQSDR. The Quisk SDR waterfall gives a good overview about the band and aircraft scatter can easily be identified.
For 13cm my transverter masthead box with the 75W amplifier was used. Its the same that was already used first last year. Together with a PTT splitter it was possible to connect my old 5W 9cm system to the same 1m dish as well. This was working better as expected.
On 6cm we had a very well working system with a old IC202 as IF transceiver. Despite not beeing used for quite some time it was still doing great.
For 3cm the feed was missing unfortunately and so we skipped the band entirely.
Surprisingly all systems where up and running at the beginning of the contest.
The focus was planned to be on 23cm because this band counts for the DARC CM. All other bads where add-on for the DARC UKW Contest Pokal OV competition.

23cm right, 13/9cm and 6cm left.

23cm place with SDR PC right and log left.

place for 13, 9 and 6cm operation.

The activity saturday afternoon and sunday morning was quite good. But i had some impression that the activity from OK which was always great is somewhat declining in the recent times. Its a bit compensated by the IC9700 effect.
In addition to the microwave activity i was planned in for some lightwave tests saturday evening. Jo DL3ARM does a great job motivating an increasing group of enthusiasts to try communication with visible light. So i took my old laser station to the hill. The decision was absolutely good since the weather turned out to be almost perfect.
Jo was on the Fichtelberg JO60LK which is only about 20km from our location. We found each others light very fast and completed the QSO in AM within minutes even during the sunset. It was great to hear his modulation and i think it was my first voice QSO via light. I took a short video of his on-off beacon signal demodulated at my station. The loud noise is some 70cm APRS on the talkback frequency we had choosen.

The next foto shows my red light as seen by Jo DL3ARM on Fichtelberg.

My light from JO60OM as seen by DL3ARM in JO60LK

After that QSO i had an unsucessful attempt with DM5D (Wetterberg) and DL3ALF (Trageser Halde). During investigations later the next week i found that the path to DM5D is unlikely to work due to going through trees in between. But the path to DL3ALF should have had perfectly worked. The problem was likely that our preparation had room for improvement. From Trages you cant see the chimney in Chemnitz which is a prominent landmark due to its colorful lighting in the night. This and the cold wind and darkness on the tower there makes it very diffcult to find the right direction. Therefore we missed this slot.
The path to DL0MLU on the Petersberg close to Halle seems too far as well. But one more QSO i was happily able to complete. With DR7B (Rene DL2JRM) i was able to complete a very nice 65km AM QSO after some minutes of mutual searching the horizont. This was a new light ODX for myself and i am very happy about that. Unfortunately i missed to take a video :(
After storing away the light rig i continued with 23cm to about 0030UTC. Then there was nobody to contact anymore in the ON4KST chat and i decided to take some sleep. I only started operation again from lunch to the end of the contest.

The result with claimed scores is:
23cm: 89 QSO (some dupes), ODX HA8V 680km => 3rd in DL SOP
13cm: 25 QSO, ODX ON4CJQ/P 580km => 4th in DL SOP
9cm: 14 QSO, ODX OE5VRL 240km => 4th in DL SOP
6cm: 10 QSO, ODX OE5VRL 240km => 1st in DL SOP
Light: 2 QSO, ODX DR7B 65km => 2nd in DL SOP

Next time will likely be only some QSO from home in July.

Some maps:

23cm 23/06 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

13cm 23/06 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

9cm 23/06 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

6cm 23/06 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

22/05 VUS

Some participation in the May VUS contest Saturday night and Sunday. Worked from home on 70cm and 23cm. Conditions were quite ok but few station calling cq.

70cm 22/05 – Kartendaten: OpenStreetMap-Mitwirkende, SRTM | Kartendarstellung: OpenTopoMap (CC-BY-SA), DL4MFM log analyzer

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.

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:

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

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

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

Some QO-100 trials

This weekend i did some new trials with QO-100. In the picture you can see parts of setup i used. This time the TX setup was purely classic. You can see it in the grey box in the foto below. FT-817 on 2m as IF followed by an upconverter made from some old UMTS measurement equipment block (silver box in the middle). It does dual upconversion with high-side LO. The LO consist of an ADF4351 each (the two smaller boards above the converter). The reference is a 96MHz OCXO of G8ACE design (left of the PLL boards). The converter block generates up to 200mW on 2.4GHz. I drive a WLAN PA (black box) that probably generates 1W. And the final PA is a MRF21030 PA (on the big heat sink on the right). It provides about 10W in SSB. The antenna is my 60cm offset dish with the DJ7GP patch (the one that has the round patch element). Left to the grey TX dish you can see a black 40cm camping dish with Octagon LNB and TCXO modification. But instead i used the BATC websdr this time. The reason is the amount of cable i currently have. I use 3 power supplies (28V, 13.8V, 5V). Reducing the number of required cables is one of the next steps. However i was pleased to do some nice QSO.

QO-100 setup

Modification of chinese 6cm PA

Since quite some while there are 5.7GHz PAs intended for video transmission from drones to ground. Those PA are made with 5GHz WLAN IC and very cheap (below 30Euro including shippment). These PA can be used for 6cm amateur radion but need some modification upfront to generate a usable amplifier.

PA6cm 2.5W top side view

The PA comes with heatsink, small fan and a short power cable.

PA6cm 2.5W bottom side view and technical info

The PCB side has a metal cover that has a sticker with some technical data. The PA is supplied with 12-16V. It is intended for 5.7GHz operation. The sticker also mentions 2.4GHz but the PA will not work there. The specified output power is 2.5..3W although the vendors usually state 5W. You will not reach 5W.

PA6cm 2.5W with metal cap removed

Removing the metal cover shows that the PA PCB contains two Sige 5004L WLAN amplifier IC, some splitter/combiner, an input attenuator and a power supply circuit. The connectors are Reverse SMA (RSMA) and they are mounted really poor. I would not even try to use the PA with those connectors and the air gaps to the PCB.

PA6cm 2.5W RSMA connectors removed

Now the silly RSMA connectors are removed. The pads need to be cleaned. Also clean the ground ring to prepare re-assembly of the shield later on.

PA6cm 2.5W with new SMA jacks soldered

Solder some new SMA connectors. The grounds of the SMA connectors shall touch the top side of the PCB. You need to shorten the ground connectors a little bit. Likely you do not have connectors intended for the PCB thickness. You may solder the other side for mechanical reason. Solder the inner pin of the SMA last in order to prevent breaking the RF trace.

PA6cm 2.5W PCB removed from heat sink – no thermal paste

Some attention needs to be put on the thermal conductivity between PCB and heat sink. Removing the PCB from the heat sink shows that cost optimizations safed the thermal compount which makes the heat sink almost useless. So add some thermal paste to the marked areas below the amplifier IC. Probably the switcher IC needs some cooling as well.

PA6cm 2.5W location of input attenuator

The PA PCB contains a input attenuator. The default attenuation is around 18 to 20dB. If you have less input power you might want to change it. For my measurements i removed the 3 resistors and soldered a 0-Ohm upside down to the middle resistor position. After everything is modified and tested you will likely want to re-assemble the metal shield.

The PA has about 27-28dB gain and my sample achieves 3W output at 7dBm (5mW) input and a current of 1.3A at 12V. Saturation might be somewhere at 4W with 10mW of drive and 1.5A current.

Input/Output power [dBm] and gain [dB] after all modifications of the 6cm PA

June 20 Microwave contest

I was working the contest from home and part time. The 23cm transverter with 10m IF and the HiQSDR work pretty well. I used the Quados4 antenna since the 36ele ordered was still stuck in customs. ODX was HA5KDQ and in total 41QSO and 6900 points raw score. I also made some QSO on the higher bands on request. 3x 9cm, 1x 6 and 3cm each.

23cm map of reached contacts by dh5ym during microwave contest june 2020