Andy (@MM0FMF) and I took a good WX window to head up Deuchary GM/CS-108 just north of Perth, Scotland.
Despite my efforts to stay out longer and operate more bands longer my 857d’s mic started failing. Not sure what the issue is/was but apologies if you responded to my CQs and then heard zippo from me.
Great operating location, beautiful walk, a little chilly (~32F) with a biting wind.
Despite being a boat anchor the 100w from the 857 is very welcome.
The Yaesu mic issue was discussed last year in this thread - Which Radio in Winter? KX2 vs 817/8
Your audio was starting to get a bit rough when I spoke to you, but as you know it deteriorated and the output power diminished. I bought a spare mic after it happened to me, but I don’t actually carry the spare up hills… it’s more for multi-summit activations where I can swap mics when back at the car. Then there’s always CW. 
I should have run over and “stolen” Andy’s 817 mic as he was happily CW-ing away.
I’ll read the thread but in the interim I wonder if a bit of clingfilm around the mic would keep rain or breath moisture out without out impairing the acoustic quality.
These are not problems I have ever had in the ultra dry western USA desert like world. My Yaesu hand held mic died in the summer due to a bit of Scottish rain.
Paul
The standard insert in the Yaesu mikes of the day were dynamics, which are basically a little speaker, with a cardboard or similar cone material. Get that wet and you can say goodbye to any flexibility or strength. I think some other failures were open circuits in the coil that produces the emf when it moves in relation to the permanent magnet.
The most common fix is to swap out the dynamic and add an electret element with of course a small bias voltage for the electret and a preamp to bring the level up to dynamic level (huge). There is an improvement in voice quality, which is welcome as the original mike was very easy to overload by talking too close to it. Lower frequencies from the voice would flat top and the higher frequencies could not activate the cone. Peter vk3ye published a how-to article on his website.
Andrew VK1DA/VK2DA
I did that with the FT-817 MH31 mic and it works great. I bought a SOTABeams compressor but it was too much with both in the mix.
I bought the electret DTMF mic for the FT-857 and have never had an issue, but it does get covered in moisture so maybe even a sock over the top (or something more high tech might stop the moisture from penetrating into the mic so easily.
Mark.
Hi Paul.
Despite your microphone problems it was good to get an s2s with you yesterday. Thank you.
73 Allan
Agreed Allan and thanks for initiating it.
Paul
I never thought to suggest the 817 mic as I only worked 3 SSB stations at the end of the session.
The other problem we had was the track to the car park has been closed off. The car park and track were built when they were harvesting trees but the estate blocked the track with 3 boulders probably weighing a ton each. The new car park was wonderful, space for 8 cars and a nice track to it. Locked gates stopped you driving further.
This is last year, so much space for cars to get them off the narrow public road…
It was a great resource for walkers, whom the estate welcomes. But obviously they didn’t like something about people parking and have stopped it. We chatted to a local gent out for a walk on the way back who described the estate “as being very petty” to block it off. Anyway, we parked in front of the boulders and off the road. There’s little parking otherwise. 0.5C at the car park so we had plenty of clothes with us. It’s about 350m ascent so should be -2C at the top or so. Paul had his 857 and big battery which equals 1 Anvil in weight which was so much more than his KX2 it slowed him down a bit 
I think it took 1hr30 to the top. My GPS decided to switch itself off on the walk up and Paul’s GPS watch was play silly bu**ers as well. But it wasn’t a strain or rush. There was no wind till we were at the top and it was cold with the windchill but fine out of the breeze. In those photos I only had a fleece on over a long sleeved walking shirt. I was cool by 1400Z when we packed up.
Paul used his 80/40/30/20 SOTAbeams dipole on a 7m pole I think. I used my 40/30/20 trapped EFHW with my AA5TB match box and 2m of counter poise. I went high and did mainly CW on 28, 24, 21MHz. Paul did 40/20 SSB. There were few chasers on 10m despite being spotted by RBN in the Canary Isles with a big signal. 12m and 15m were good with a nice constant stream of chasers. ODX was WW4D on 15m CW at 6224km.
The paths up were well frozen and it was nice and gloopy and slippy on the way down. I’ve seen proper mud here and thigh deep snow, so the frozen paths were nice on the way up.
My setup, 5m pole, EFHW, FT817
View to Schiehallion GM/CS-005 (it was murkey so this has been played with)
All in all, a good day out walking and playing on the air.
What model number is the electret version as a quick Google shows up scads of dynamic versions?
Hi Andrew
Thanks for the heads up. I have some Electret mics from Adafruit back home in California and will try the upgrade.
Oddly enough ML&S (UK dealer) have MH-31 for about $40 plus shipping (out of stock) and DX Engineering (US dealer) for $66 plus shipping (in stock). UK cheaper than US must be a first!!
Paul
Hi Paul
I meant to say dynamic - as in powered. Shows you what I know about microphones!
Other way…dynamic is zero power and electret is powered.
Paul
So is dynamic the same as condenser, or are there two un-powered variants.
This is the one I bought:
Dynamic is typically a coil moving by a magnet. The sound moves a diaphragm attached to the coil. The coil moves in the magnetic field and makes a current which is varies with the sound. A condenser mic is a capacitor with one movable plate. The sound moves the plate and is it moves nearer and farther from the fixed plate the capacitance changes. It doesn’t generate any current so you apply a voltage and the changing capacitance varies in time with the sound.
If you have a radio with a dynamic mic, you can use a condenser mic (or electret) if you provide some DC to energise the mic element.
Mark,
You’ve just confirmed that the MH-36E8J does exist and the vacuum on Ebay is anomalous. I have one of those mikes and the cable “grommet” for preventing excessive stress on the internal connector and the cable has fallen apart, seems the synthetic rubber used for it was degraded by time, it certainly wasn’t due to over-use as it was in my spare 817 pack and had never been used in 10 years.
Re electret and condenser mike elements, yes basically similar in that both require a bias voltage. Some radios now have a hardware or software switch to provide the bias voltage, to suit the microphone type.
The output from the electrets is very small and an amplifier is required to bring the audio level up to something near the level of the dynamic mikes, to keep the signal to noise ratio good on the cable. Similar mikes are in mobile phones etc. They are very small but have amazingly good quality and frequency range. And no resonances which was a typical feature/drawback of the dynamic mikes.
73 Andrew VK1DA/VK2DA
Confession: I didn’t have my reading glasses on and was looking forward to reading about the “Debauchery on GM/CS-108”…
Cheers,
Jeff KX6
Hi Paul,
I’m a CW guy and don’t do much phone these days. Well, except for S2S opportunities. I use my old iPhone earbuds with built-in mic with a special adapter cable for my KX2. It works great but I do have to hit the xmit button on the KX2 when I transmit on phone. I don’t use my original KX2 mic as it’s way to big to carry in my relatively small container for all my radio gear. I’ve also had a mic failure when I used to carry an 817 (before I moved to CW). Not fun when you spent a lot of effort getting to a peak!
It’s best to have options for both CW and phone modes – I know you already know that and I think you’re still working on your morse code! Good luck my friend and I hope to see you back in Colorado some day!!
73, Brad
WA6MM
Thanks for the heads up on the car park planning this one next weekend
You can park at Dowally, the walk is a bit longer and bit more ascent. From Dowally, the route meets the route from Guay. PM me and I can send you a GPS route etc.
