Went the day badly... Hart Fell GM/SS-037

Actually a bad situation was recovered the next day but…

WX forecast was for “scorchio” sun over the South of Scotland with hot temperatureson Friday and the weekend weather not so good so I took a day’s vacation out of my huge stockpile for Friday and then posted to the gm13 group to stir up some 13cms activity. As the WX looked good, may as well do a decent walk I thought. In the end Hart Fell GM/SS-037 selected itself. gm13 produced responses from Jack GM4COX on Meikle Bin and Andrew G(M)4VFL on The Merrick. Brian GM4DIJ was also going to play from his /A QTH down on the coast near Luce Bay.

I’m out of practice estimating driving times and walking times so I accepted what various bits of software said and added a safety margin to get a must leave home time. There was hardly any traffic, more like a Sunday morning that Friday morning, still lots of virus impact in Scotland though there were plenty of caravans and motor homes on the motorway. I was doing Hart Fell from near Ericstane and there is parking at the village hall for 6 cars. 1 car there when I arrived early. Good a leisurely setup I thought.

For 13cms I need the transverter, its power cable, IF lead, antenna lead, 13cms antenna, reserve antenna, PTT lead and an additional battery. I swapped out the LF antennas for my holiday HF dipoles which are lighter. As it was meant to be hot I added an extra bottle of water. The idea being to loose weight elsewhere to allow for the weight of the 13cms gear and more water. It was very gloomy and not at all like the forecast but I checked I had suncream in the bag and applied a good measure anyway.

There have been big changes since I was last here for a UHF fun day in 2011. The lower slops of Hart Fell have been planted with mixed broadleaf and pine trees and there is a substantial deer farm at the bottom. Deer farms mean deer fences and I don’t like climbing over 8-12ft fences, it’s dodgy and ungainly. Luckily there are plenty of gates and proper paths to skirt around the enclosures. That earns a :+1: for the farmer.

Lower field of 2 full of deer including either a fully piebald or dirty albino deer.

It was hot but easy work but at the back of the second deer field the climbing starts through the new forest. The grass was long here and plenty of bracken too. Deer and bracken… check for ticks later. There’s a good path and the planting is such that it will be possible still in 30 years time should I still be climbing hills in my 80s, more later.

Looking back third of the way up and the steep climb over.

The clear ATV track to the top. It’s not particularly steep, just a slog over easy grass.

It’s just a long slog to the top. I was feeling my lack of fitness and the heat but the wind picked up which was good. Slowly the cloud was lifting and it was a good blue sky with some fine high altitude cloud by the time I got to the top. First job, a good drink. Then start the setup. I deployed the HF gear then a 2m FM J-pole for talkback / coordination then the 13cms antenna. Then all the wiring for the transverter, then the 817. Final job was to get the two batteries out for the 817 and transverter. Disaster… only one battery. Now I had 2x LiFePo, 2x LiPo and some 18650 LiPo packs in the car and gone to lengths to get two batteries out ready. Then I only put one in the bag. When I got back to the car the second battery was separate from everything waiting to be packed.

I wasn’t going to give up after 2h15 walk over 6+km and 650 ascent on the hottest day of the year. I set about cutting off connectors and striping wires so I could connect both to the battery. It was a 4200mAh LiFePo so should do the job. A quick check and everything was working and GB3CSB 13cms beacon was coming in at 59+. On with the handy and a quick blip to check and hey what’s this… why is it saying “low” and flashing the battery symbol? The voltage said 7.6V hit PTT on 5W and the voltage collapsed. Onto 2.5W and the voltage stayed about 6V and no warnings. Hmm after 12years the NiMH pack on the VX170 is failing. OK, we had talkback.

Setup for 13cms, 2m and HF (dipole legs disconnected here)

Trig point on GM/SS-037. This is one of the oldest trigs in the UK and is in amazing condition as it’s been here since 1937.

SMS received Jack was QRV. Meikle Bin is the same direction as GB3CSB, text Jack to call 2320.200. There was Jack talking to someone on 13cms. A quick QSO 59 both ways and Paddy MM0JOX was the other station. Easy 57-59. That was a bonus QSO and with Andrew going to be a 3rd QSO it was possible a qualification on 13cms could be had. Monitoring on 2m and Andrew G(M)4VFL appeared on The Merrick on 2m, bagged and then Roy GM4VKI was bagged on 13cms. I could hear Roy just in QSO with Jack and when I was talking back Roy peaked on me so after he was a simple 52 QSO. The direct path would have worked in CW with a narrow filter but our QSO was completed by Roy beaming at Goat Fell on Arran and bouncing the signal. No surprise 13cms is a popular RADAR band !

I worked a few on 2m whilst Andrew did 2m then 4m. Finally we worked on 13cms FM at 55-57. It’s a slightly marginal path with Carlins Cairn to the North of Corserine GM/SS-033 being a few metres low enough to allow the signal to be easy, just. Qualified on 13cms. Andrew had worked Brian GM4DIJ and we tried to coordinate via Andrew to work Brian. No go. I worked a few on 2m and was going to call on 2m until the batteries died in either rig but Jack sent me Brian’s number. A text later and I was ready to try again on 13. I’d pulled the power lead out when just on 2m to save battery.

Disaster #2! Plugging the coaxial power lead I found the tip (+ve) is exposed and it touched the metal case of the transverter. Click. 817 went off. Oh dear. Hacking the cables to get both working the absence of two batteries meant there was an unfused path. The +ve of the battery lead was connected to the case of the transverter. The -ve wasn’t connected but the IF lead connected the -ve through the screen. That screen will carry a lot of current. The fault current makes its way across the 817 circuitry to the -ve cable at the 817 to the battery and ker-boom! The classic failure is the common mode choke melts and a track by the power socket lifts. Bugger!

That sort of spoilt the day which had been going well. I took some photos, had a drink and packed up.

White Combe GM/SS-030

Broad Law GM/SS-029 (both the police tower and the VOR beacon are visible)

Culter Fell GM/SS-049

Tinto Hill GM/SS-064

It’s just a long slog back to the car. When I got back I found the battery waiting to be loaded. Ha! The car said 26.5C so it was AC to max whilst I drank water and then Red Bull. On the way back I was annoyed that I had killed the 817, not hard to fix but unwanted fun and games. I was stunned that Andrew’s dad had climbed the Merrick with him. Andrew’s dad is 93. That’s quite an astonishing achievement.

Saturday morning… I cleared the workbench and checked no continuity in the -ve lead to case, something is OC. I stripped the 817 and removed the main board. It’s not difficult but fiddly. No damage visible. Continuity checks were fine too. Check the power cable and the wire had melted at the battery connector which was only visible once the heat shrink was removed. The +ve failed a few weeks back after 11years strain damage and the -ve must have been on the way to failing which was why it was able to act as a fuse. I spent 15minutes swearing whilst trying to get the main board back in place and remade the connector and full 817 service was restored. Finally I fixed the transverter cable.

What did we learn Andy… fuse both leads not just the positive. I know this but as I always use 2 batteries the particular fault condition that caused the problem can’t happen. But with one battery… setup to fail! I’ll take the embarrassment of knowing what to do and not doing it so that you don’t do the same.

Still qualified on 13cms, 817 repaired for the cost of my time, new battery for VX-170 to order. Oh, and some new legs needed. I’m rather stiff after 12.5 km and 650m in 20-26C temperatures.


That caught me out once on Plynlimon GW/MW-001, with the 23cm SG Labs transverter - same power connector with exposed tip. Luckily just a fuse, and I had a spare! I’m now always careful to connect that end before applying any power.

Enjoyed your report, and a happy ending too :o)

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Your report here makes me think my experience is very pale in comparison.

Its great though to read what others experience and how it was resolved.

The photos are great as well. Really adds to the experience.


You might consider placing two power sockets on the battery lead, so one battery can supply two devices. If you use a standard power connector this can work very well. I put a pair of powerpoles onto my batteries and that has been handy when I want a radio, amp, transverter and possibly an ATU, well, two at a time from one battery. A 4.2 AH LiFePO4 battery can source up to 90 amps so there’s no problem running several 1-2 amp devices. With two sockets permanently on the battery, it’s impossible to forget the adaptor, a well known SOTA risk!

Well done retrieving the activation from a possibly flame-out, glad the radio wasn’t damaged. As you say, this is why a fuse is advisable in both leads from the radio.
73 Andrew VK1DA/VK2UH

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What doesn’t kill us makes us stronger. Or poorer if the radio had been fried extensively!

That’s a neat fix which I hadn’t thought of.

Hi Andy -
Yes, the coaxial plugs provided with the SG-Lab transverters have exposed +v - I’ve made nice sparks several times when bumping the case whilst connecting the battery. Fortunately my BioennoPower LiFePO4 batteries have an integrated PCM so I just waited a few minutes for it to reclose and was back in business.
For the SG-Lab transverters I use a band to keep the connectors inserted, but perhaps it would be even better to use connectors without exposed +v.
Wonderfully told story Andy - I enjoyed it much…
73, Etienne-K7ATN


this is my double socket on the battery lead. This also solves the problem of what to do with all the strands of wire in the original lead from the battery. split into two sections, each fits in a 30 amp powerpole lug.



Excellent report Andy. Well done on the 13cm qualification, even if the day was beset by problems. Hart Fell is one of my favourite hills in that area, probably because it was the first sizeable one after my heart attack and so an achievement, for me at least. :grinning:

Friday was hot here in the Midlands… ramped up to 34C with the usual humidity. Not my favourite weather to say the least. I should have headed north!

73, Gerald

Thanks for you after-action report. I really enjoy reading about the experiences of other operators, particularly those who describe both the successes and failures! That allows me to learn vicariously through their experiences, such as your description of what went wrong and how you managed to carry on.

I made the hike up to W7N/TR-007 (short hike) and enjoyed my trip as well. I also learned a few things on this trip.

I’m looking forward to more stories. Thank you.

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