Shining Tor 01/08/20

Was a fun afternoon activating Shining Tor G/SP-004.

Thank you to all of the chasers who always make the journey to the summits so worth it.

All week when I have been planning this activation the weather has said it is going to be sunny all day. This morning I put my walking trousers on but remove the legs so I have shorts on, its going to be nice weather the weather man says. Wrong! No sooner had I arrived at the base of Shining Tor, I could see the weather rolling in from the distance. So glad that I packed my waterproof coat otherwise this could of been cancelled. So I have had 4 activations 2 in wet weather and 2 in sunny weather.

I had a few summit to summits today most notiable for me was Vicky MW6BWA/P as I have seen her post around the group before as well as her xym. Shame for MW1HAX/P both of us was calling him but he was unable to hear us.

Strange to not hear Tom today. I was looking forward to a qso with him, maybe next time.

My SOTA activation went as planned I bagged 25 fm contacts from the summit. Then everything went downhill fast. i changed over to the yagi and got it at 6m. plugged in the Yaesu 857 went to power it up, nothing. checked all of the connectors no issues, still no power. Checked the cell info on the little gizmo thing and noticed that the voltage had climbed to 16v when charging. Funny as the batteries are supposed to be just 14.8v at full charge.

Got back to the qth and checked the battery output on the multimeter and it is now 17.1v Batteries are currently on discharge and on Monday i will be questioning the vendor as to why my 14v batteries are at such high voltage. They work fine once the voltage has been reduced to 15v as well. Shame as they are 7600mAH.

I look forward to the next activation next week.

de M6UUH

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Those voltages are normal for any 4S Lipo battery. Lipo Voltage Chart: Show the Relationship of Voltage and Capacity - Ampow Blog

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Are you referring to Tom M1EYP Iain? If you are I am his son. My dad as of today is on a SOTA trip and will be until the Friday 7th August doing as many SOTA activations as possible for the 17m challenge. You will see some spots for him today on some summits in Wales round the Welshpool area and also one SOTA summit in Shropshire also. The best chance of working my dad this week is to work him summit to summit on 17m.

Jimmy M0HGY

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I am indeed Jimmy. Hope to work him at some point that’s for sure. Fingers crossed for him on the challenge.

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I never knew that. But now I do I know to never charge past 70% on each cell. I did try a buck converter last week to no avail. The converter was rated at 25a apparently. It failed with the 857 and that calls a maximum of 22a when transmitting. Thank you for the link though.

You may also find this helpful

http://www.rogershobbycenter.com/lipoguide/

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22A when transmitting at 100W. At 10W it will be somewhere around 6-10A max,

Use a bridge with a bit of aluminium plate for a heatsink and a coupe of switches to short out the diodes when not need.

Hoooooo! You’ll never get that on a plane :wink:

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I have just ordered one Andy and shall see how we got. I have some spare heat sink anyway from the failed buck converter so I shall just use them. Thank you for the advice. I was looking at the full Amp pull, no so much for now but for when i move up the licences I might want to use the avaliable extra power, although 5w is plenty at summits.

I never really thought about getting the batteries on a plane, I also think that until the whole Covid-19 pandemic is over, I dont think ill be getting on a plane or until its at least better managed. Then hopefully LiFePO4 batteries will be more avaliable.

Update

I have received the Bridge rectifier and built the necessary leads. All connected and put in an IP65 box with the correct in and out.

Works a treat, all my batteries are putting a nice 15v and below out to the 857.

I have tried it a number of times as this will not be haunting me again.

So my next summit, maybe this weekend will definitely involve 2m SSB.

Thank you all for your helpful comments. Sota is definitely teaching me a lot and I am managing to put some of my intermediate training into practice, soldering etc.

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