Icom Remote Utility Issue and Hamlib

When running JTDX (version rc155 with the ic-705 supported) and the Icom Remote Utility I kept getting annoying errors from HamLib which made it unusable.

Hamlib error: Protocol error while getting current VFO frequency
Hamlib error: Command rejected by the rig while getting current mode

It seems that if you turn OFF the CI-V Transceive option in the Connectors->CI-V menu this fixes the issue. All problems went away, however I did need to restart the Icom Remote Utility.

I assume Hamlib wasn’t handling the returned ci-v commands with the ci-v transceive setting enabled. This may be the case on all Icom radios, not sure, however it is a default setting on the ic-705.

73 Richie.


GB19SG Portable

I was fortunate enough to be able to operate GB19SG for the Cricket World Cup RSGB event, the call being managed by Rich GW4BVJ. As a member of the small team I operated many times from the home QTH, friends QTH on both SSB and FT8/4, and portable. It was very enjoyable indeed. Below are some pictures from the portable activities. 73 !

Grosmont, Abergavenny – IO81nv 13th + 14th July 2019

Magor Wetlands – IO81nn – 10th July 2019

Magor Wetlands – IO81nn – 28th June 2019

Categories Uncategorised

Multi Band Vertical – Part 1

So, unless you have been living under a rock you will have heard of DX Commander. M0MCX, Callum, runs a micro antenna business producing mostly multiband vertical antennas. He also runs a very enjoyable YouTube channel.

Based on a ‘fan dipole’ idea, half of the the dipole is taken and turned on end, and driven elements for each band run up a vertical fibreglass flag pole. With a suitable ground system deployed a multiband HF vertical can be achieved very quickly. Research paper after research paper shows that diminishing returns are reached with roughly 4 times the amount of copper down as the wavelength of the lowest frequency band. So, if you want to reach those diminishing returns on 20m for example, you need something over 80m of ground radials, and don’t stress making them 1/4 wave or anything, just any old length, 20 to 30 radials of 4m each would be fantastic. Just chuck them down and get on the air !!!!

Anyway, with the ‘technomagic’ aside, I decided to built my own home brew version. I am using an aluminium plasterers hawk, upturned to act as the ground plate to attach all the radials to. Drilled and tapped, suitable bolts and an so239 attached, it is very easy to deploy. A couple of holes can be made to push tent pegs through.

I picked up a DX Commander 10m fibreglass pole. The end cap can be removed and it sits nicely over the handle from the plasterers hawk.

In Part 2 I will build the ‘spacer plates’ and get the elements cut for each band I want to operate on.

73 for now !

ICOM-7851 RFI issues

A quick follow up.

So, my friend had problems with his IC-7851 doing strange things. After hours of diagnostics the issue was found. The interlink cable between the STEP-iR control box and the CI-V port on the back of the radio seemed to be causing the USB disconnects and other gremlins. With the interconnect removed, all problems vanished.

We tried ferrite after ferrite on that cable to no avail. Either the early generation STEP-iR control box has insufficient RF attenuation, or there is some other issue, perhaps with the ic-7851 or the data/control cable from the tower to the STEP-iR control box. Either way, with the interconnect removed, and consequently no auto control of bands, then the problem goes ‘away’.

73

ICOM-7851 musings

A friend has been having some issues with his new, rather gorgeous, ICOM flag ship radio, the IC-7851. CAT issues, com port issue, cw keying issues, STEPir tracking issues. This post is really to act as a record, and perhaps help anyone else with similar problems. All related to configuration, possible conflicts and other such annoying gremlins.

So, after removing the icom usb drivers, unplugging the usb cable, and reinstalling the drivers, then reconnecting the usb cable, the radio and computer seemed happy. COM7 and COM8 showed up in device manager. However, there does seem to be an issue where upon reboot, sometimes the USB devices will not be recognised. This issue is to be monitored and some more work perhaps required figuring out what is happening.

Moving on, we managed to get the radio talking to HRD and Logger32, at 19200 baud, 8n1, no handshaking, on COM7.

We then looked at CW keying over the USB cable, instead of running a separate cable and related serial interface. The IC-7851 presents two com ports as mentioned above, COM7 seemingly the CAT control, COM8 the keying port perhaps. Another friend did mention that COM8 might be second RX, but not entirely sure on that. Anyway, COM8 was used in the keying config of Logger32, and the 7851 was configured to use USB2 DTR as its CW keying source. All worked great, with CW and break-in selected on the radio.

We then looked into getting the STEPir auto tracking the vfo frequency. The STEPir control box is quite an old version, pre-dating the current SDA100’s. After much head scratching, we decided to use the remote (ci-v) port on the radio. The TIP of the 3.5mm jack, going to PIN9 (ttl rx) of the 9way d-type female that plugs into the STEPir box, and the RING to pin5 (gnd). A quick solder job and it was all working. Note: the pin out of the STEPir 9 way is not standard serial, certain pins are there to be connected to different makes of radios.

3.5mm mono – 9way d-type female – CI-V to STEPir

It has been noted that the STEPir will only track when the vfo on the radio is adjusted, and not when Logger32 tells the radio to move frequency. The IC-7851 needs to have CI-V transceive turned on.

Some configuration settings recorded here as a record.

73!

current IC-7851 settings

Tannoy Reveal 502 issue

So, one of my Tannoy Reveal 502 speakers kept blowing its T500mA fuse. I purchased some replacements, tried a new one, and pop. Something was obviously wrong.

The cabinet was a bit awkward to open, but I needed to get in there and have a look. The outer screws removed I poked something soft(ish) through the front port and ‘persuaded’ the back panel to come loose.

After a quick visual inspection I noticed that C11, a 100nF decoupling? capacitor, looked very hot and burnt. I did a quick check at this point and sure enough there was a short somewhere on the +ve and -ve rails.

Out with the soldering iron, I removed C11 and C6. C11 disintegrated as it was being de-soldered, and was obviously defective. I also removed the two 3300uF caps and gave them a quick test, they seemed fine. With those two re-soldered as they were ok, I replaced C11 and C6 with some 104’s (100nF) ceramics, and ran some tests with a new fuse in place. All seemed to working fine, sounding great. I left C6 and C11 on long legs to move them into some free air to try and reduce the chance of over heating. The yellow ‘hot snot glue’ was a nightmare to remove and was more like epoxy.

I must say, the ‘psu’ board did not seem to be of high quality. It looked as if it had been put together on a Friday afternoon, caps at all sorts of angles, rectifier twisted, just shoddy workmanship. I didn’t remove the amplifier/filter board so I can’t comment on that.

Anyway, a simple fix and I once again have a right speaker ! Happy days.

MB7TR – SSTV repeater

We have a new local SSTV repeater, and as far as I know one of only two in the country. Classed as a ‘regenerative node’ it will relay/repeat a received image.

MB7TR is situated in Cwmbran, and maintained by MW0RPB (Peter). It operates on 144.500MHz using FM and outputs in the Martin1 sstv mode.

To get it to repeat your transmitted image, which incidentally can be transmitted in any SSTV mode, you need to do the following, all on 144.500MHz in FM :

  1. TX your CW ident (good practice)
  2. TX a 1750Hz tone burst for around 1-2 seconds and key off
  3. Listen and wait for MB7TR to reply with its CWid – this signifies it is ready to repeat
  4. TX your SSTV image
  5. Sit back and wait for your image to be repeated out

You can use your SSTV software of choice, MMSSTV being mine. It is working great, after a few teething problems Peter has ironed out all the gremlins. Give it a try, you never know who might reply !!

GB3VHF signals

Well after having the new 13ele tonna up for a couple of weeks I recently noticed a signal around 144.430Mhz. After some quick research I discovered it to be beacon GB3VHF which outputs a JT65B signal.

I can copy the beacon on the beam S5-S6 seemingly 24hrs a day, so quite a good path between us. SNR’s of -1dB to -2dB in WSJT-X are the norm. I decided to listen with the x510n collinear vertical and to my surprise I could decode it with varying snr’s.

I ran it from around 3am on the 21/05/18 through to mid day, recorded the results and plotted them. You can easily see that the SNR improved from around 6am through to around 8:30am.