I had a slight problem with the antenna relay not making reliably on receive (solenoid energised). I just upped the supply volts a fraction of a volt and this seemed to settle the relay and not upset anything else.
I failed with my first attempt with Jon GM4JTJ as I was too weak for him. We made it on a second try later. I didn’t hear any stations on the continent.
This was my first UKAC this year. The Microwave Modules 70cm transverter wasn’t working on PTT for some reason and was defaulting to RF Sense, so I struggled a bit on 13cm. It is nice to have 13cm going again. I need to improve the Noise Factor of the pre-amp in the box on the pole, but that will have to wait until the weather calms down.
It was all pretty local stuff on 13cm:
It was even more local on 3cm:
I hopped about between both bands. On 13cm it was was nice to work Pete G4CLA again. Keith G4ODA was my best DX (longest distance) at 117 km. So my contacts were all pretty local really. I used 25W into the coax to the antenna box, so the Andew amplifier was under-driven.
On 3cm, my initial contact was with Peter G3PHO. Our usual reflection point worked well to get round the hills. Keith G4ODA was my best DX (longest distance) on this band.
The rain was in the wrong places for rain scatter.
Denis G3UVR was much easier to hear on 3cm than on 13cm, and the dish is mounted a bit lower down than the 13cm yagi.
With the SG-Labs 13cm transverter in a box indoors, I can use a sub-band switch on the front panel of the box to switch between 2.30, 2.32 and 2.4 GHz. At 1870 MHz, the LO (Local Oscillator) frequency is rather low for the Microwaves Modules 70cm transverter (1870+430=2300 MHz) as I have not reprogrammed the SG-Labs transverter, so I thought the configuration might not work on the 2.300 to 2.302 GHz NoV band. I had configured the K3 with a 2300 band setting to generate the correct frequency on 10m band Intermediate Frequency (IF) feed to the 70cm transverter.
Using my Tiny VNA as a signal source, I found I could receive in the 2.30 GHz band.
I tried a contact on transmit with Keith G4ODA. It worked easily! Keith’s signal was very strong. I was using the Andrew linear amplifier producing about 50W, feeding the 40 el Wimo yagi through some metres of Ultraflex-10.
Really the SG-Labs transverter needs re-programming to give a more appropriate LO frequency, but it is nice that something works on the NoV band for the time being.
UK radio amateurs can apply for an NoV here for the 2.300-2.302 GHz band.
Whilst in the middle of printing, I accidentally touched the turn-off button on the printer & after that, nothing would print and the printer status in the System Settings/Printers for my ET-4500 showed as: “Stopped – Unable to add document to print job”.
I searched the printer menus, but could find nothing to help. It just wasn’t handshaking.
I deleted the printer and re-installed, selecting Network Printer and AppSocket/HP JetDirect. In the host field I typed the fixed IP address 192.168.m.n (m.n being the numbers I assigned in the printer settings). I clicked Forward and selected the test page option.
I put in an appearance in this contest. On 23cm my best DX (longest distance) was Jon GM4JTJ. I seem to have missed him off the map, but he’s there, up North! I had 17 contacts.
13cm was a struggle, with only 3 contacts, the best DX being Barry G4KCT at 69 km.
I worked a few locals on 3cm, collecting my partner from the station in between. I could just hear David G4ASR in the noise, but not strong enough to work. I had tilted up the dish a tad in order to clear the ridge of trees. Anything south is a problem. I failed with John G4ZTR. Kjeld OZ1FF didn’t respond to my meeps on ON4KST KST chat. So about 400 points on that band maybe.
I had taken the relay box down from the pole the previous day for 13cm. That Tue eve I finally found the fault. I had added an LED to show when the relay was on transmit. This drew just enough current to have the side effect of latching the relay to receive (energised), so no RF out on transmit! I disconnected the LED & the relay worked. So I just lashed it up on the bench. I worked Denis on about 1W at the antenna. Then I cabled in the linear with some attenuation to get 20-25W for a couple more. I tried John G3XDY near the end of the contest and logged what I heard. Then I timed out.
Denis G3UVR was easier to hear on 3cm.
I’ll try a low-current LED. If I get a good spell of wx, I’ll put the box back on the mast & get the pre-amp nearer the antenna. I haven’t tried the relay or pre-amp before. The Narda relay is nice & chunky, but its markings suggest it is only rated up to 1 GHz. I may have made the Noise Factor worse on receive, but I have some more dB on transmit. I’ve included a Band-Pass Filter in the box, so that worsens the NF a little more.
At least all the control circuitry seems to be working: sequencing, 12V to the pre-amp, 24V to the antenna relay etc. The 40el Wimo yagi is back up on its jockey pole so I can do terrestrial 13cm again. It has been nearly a year since I started upgrading 13cm with a pre-amp and linear.
The SG-Labs transverter is now in a box in the shack, with reverse-polarity protection, sub-band switch: 2.3 Ghz, 2.32 GHz and 2.4 GHz, power switch, ref. osc. input switch, indicator LEDs power switch and a nice Anderson power plug. I want to add drive power switching and a monitor meter.