I was wondering if one of those Z Match type QRP tuners would work without the UNUN ?

I do a bit of wild / ultralight camping with a mate of mine and have been thinking about antenna solutions when up on the hills.  I got to wondering, if I had a small QRP CW rig in my bag, but no way of setting up an antenna, would the metal tent pole tune up for emergency use ?  Imagine you are caught in a snow storm on top of a mountain and have to get into your tent quickly......

My tent has a single folding aluminium lightweight pole, about 9 feet long, that arcs from one end to the other, im sure a Z Match type tuner would tune it up ok.... although it wont be particularly resonant so close to the ground and being so short.  But who knows ?  You only need one person to hear your distress call.

So if any of you are off camping, be sure to give it a try and report back.... im off in a few weeks hopefully to North Wales and will give it a little try.  Possibly worthwhile as an experiment.

Ive just built the 40m QCX kit from Hans - and it was a pleasure to do (my 1st proper kit) , the instructions are so well thought out and the support forum is so helpful.  It worked 1st time.  I messaged Hans to ask about current draw on the new QSX, but he wouldnt divulge, except to say he was looking to keep it low where possible, but to bear in mind that its SDR based, so wont be flea power.....   I might order 3 !!!!!

ok thanks  - I read the manual but it isnt very clear and YouKits arent replying to my messages.  Hopefully VWflier will know.... :o

so Ray  (just double checking  ;) )  I can leave the battery in place, switch the unit on and let it power up with the internal battery - and then also plug in an external power source (eg. car battery 13.9volts) and it will be happy ?

Sean.

I might pick up an MTR3b for the weight saving if climbing..... the hb1b is pretty hefty with the internal battery and a touch bigger than the MTR4b - but as you say, the benefits of 80m and the SSB and power options are more important to me.

One question, can the HB1B be powered through the external 9-14volt connector if the internal battery is installed (it has a separate charge port) ?

Ive sold the mtr-4b on Ebay and swapped it out for a used You Kits Hb1b.    the mtr-4b is a nice radio, but it cant take more than 12volts DC input power, which limits its use in the car or in an emergency.   The hb1b has the same bands, but also adds SSB receive across 80m band through 20m which is a real plus too.   Add to that an internal battery (that seems to last for ages) and the fact that it was £100 cheaper than the one I just sold and its a win win.

https://qrp-labs.com/qsx.html
I'm officially excited - I emailed Hans at QRP labs about current draw - although he wouldnt commit to an answer he did say he was working on getting it as low as possible.

The perfect prepper radio ?

Ive been thinking (dangerous I know !)  - I'd like a QRP portable end fed halfwave thats reasonably short - so the 40m band to 10m band ones seem perfect for when I'm out camping and hiking (being about 20 metres long).   Very manageable and easy to sling up over a tree or with a mast.   But I also really want to be able to work 80m as well.......  So now Im wondering is there a way to get a 20metre wire resonating on the 80m band ?

Maybe a bypass switch on the feeder box that ?  maybe a coil that can be switched into the circuit.   If the end is high up wired to a tree then the match box will be closer to the radio, so flicking a switch is quite easy.  So , over to you technical bods to discuss the possibilities !!!  I dont mind a bit of higher SWR, as long as its about 2.5:1 or lower, I can fix the rest with a z match tuner.   Interested to hear your thoughts if something like this is possible.

Some interesting points there Gil - Id really like to see some of the rigs (MTR's QCX's and so on) have the option to redcuce power output.  If all I have is a 12volt battery and the transeiver is putting out 5 watts, id personally like the option to drop the power (and save some battery life ?) on the fly.   I might not always want to reach out to other continents.

As to your question about power threshold for a SURVIVAL radio then I really only need a few hundred miles distance - that might necessitate using a low, horizontal antenna for NVIS or ground wave if im high enough.

Whats special about the coating Gil ?

Quote from: gil on June 06, 2018, 04:47:32 AM
Hi Andy. I don't know about KingSolar, but I will be looking at Lensun for myself, because of the better coating they use on the sunny side...

Gil.

We got to test it in anger last night at radio club, they helped me set up the 20m end fed and one of the experienced CW operators guided me through it.   Then one of the other guys set up a HF rig inside and confirmed they were receiving a good signal - so at least I know it transmits.

I called cq for a while but no response yet ...... will try the large Multiband end fed at the house today.

Nabbed an eBay bargain I think - £207 for a mint mountain topper mtr4b, a new palm paddle, SOTABeams mountain tuner, qrp guys tuner kit, mini speaker, 20m SOTABeams efhw 20m antenna and a 7m SOTABEAMS pole..... phew... and after all that, he threw in a wonder wand tuner and telescopic antenna.  Chuffed to bits.... the guy lost interest and wanted rid of it all.

The radio is a lot smaller than it looks in the photos and easy to use..... I'm still learning the code so more of a push now to get on and have a 1st qso.

Thanks Gil,  id want something wired internally to run directly off car batteries/battery terminals  - im keen to have it all self contained if possible - I might even remove it all from the original box and re-box it with a ZM-2 (or similar)  in a single (more solid) case.... and a little active loudpspeaker and a switchable keyer.....along the lines of those project boxes youve been using lately.   Then I get options for resonant antennas, random wires and much more.

THe lithium Ion batteries - are they the 18650 you have been using.....   that was the plan for portable generally and the screw terminals for "emergency" power when required.

With an adjustable 7812 regulator I suppose I can adjust the transmit power as well.

So I've decided I really want an mtr4b...... but I'm struggling with the fact that it won't take over 12 volts like most others do.  Being able to plug into a car battery would be a key factor for the "prepper" side of my brain

Can it be modded easily ?  I was thinking I could add a second power socket for 13.8 volts but not sure exactly what parts are needed to drop the voltage.  I'd like to add a couple of banana plug/screw terminals for easy field use.  I'd keep the original power socket for smaller batteries and maybe add a switch to flip between them ?

Love to hear your thoughts.  Regards, sean.