Portable Fun

ToddDubya

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I got my ticket about 8 years ago and have never gotten over mic fright until a few weeks ago. I figured a good way to break the seal would be to hunt some POTA (Parks on the Air pota.app) activators. They're looking to make contact, exchange calls and signal reports, and move on. No pressure to hold a conversation or anything, and you're doing them a favor. So that's what I've been doing and it's a shit load of fun.

I just finished an end fed half wave for portable use. It seems to work great, but isn't winning any beauty contests. I would have liked to build KM4ACK's kit but it's been out of stock forever. So I built it from scratch onto some kydex and it mostly does the trick, minus wire winding capability. Another good option would have been the kit ARRL is selling.

Anyway, after I got the antenna trimmed to a decent SWR across the 40/20 (and quite possibly 15 and 10) meter bands I took it up on a mountain last night and oh man is it nice without an S8 noise floor. I got rained out pretty quickly so today I hiked into to another spot and set up shop. It's a contest weekend so the bands are packed, but I made 8 POTA contacts before the rain chased me away again. I wasn't 100% sure I was in a park so I didn't attempt an activation. And I'm not sure I'm confident enough to manage a pile up.

Right now I've got my Yaesu 857d and a Bioenno 12Ah battery in a backpack along with the antenna/coax. My throw line is bulky as f*** so I carry that separately but I've got something new in my amazon cart. I'd like to find a bag that is more appropriate for the task. I've seen purpose built bags for radios like the Icom 705 but not for your standard shaped mobile. Ideally I'd be able to operate without unpacking to connect everything up. If anyone has any ideas I'd love to hear them.

I've seen a few guys just using 24-hour packs that will clamshell open all the way. That might be a good solution, especially if I use an antenna that requires a tuner and need a little more room. I've seen this DDT model in a few videos.
 
I just finished an end fed half wave for portable use. It seems to work great, but isn't winning any beauty contests. I would have liked to build KM4ACK's kit but it's been out of stock forever. So I built it from scratch onto some kydex and it mostly does the trick, minus wire winding capability. Another good option would have been the kit ARRL is selling.
Maybe see if you can get a copy of the 7-page Dec'21 CQ magazine article
"A Deep Dive into End-Fed Half-Wave Antennas" by Bob Glorioso/W1IS and Bob Rose/KC1DSQ.
I think they analyze the antenna in far more detail than the average construction article.
They basically designed it from scratch, with tons of simulation and real-life testing.

Right now I've got my Yaesu 857d and a Bioenno 12Ah battery in a backpack along with the antenna/coax. My throw line is bulky as f*** so I carry that separately but I've got something new in my amazon cart. I'd like to find a bag that is more appropriate for the task. I've seen purpose built bags for radios like the Icom 705 but not for your standard shaped mobile. Ideally I'd be able to operate without unpacking to connect everything up. If anyone has any ideas I'd love to hear them.
You really don't want to bust the two small knobs off of the FT-857D.

There are lots of guys that build them into rigid boxes (look up "go-kits").

Now, the box itself isn't going to be eminently packable on its own
(especially if it's cube-shaped). Most of those go-kits are only
intended to be carried from a car to an emergency operating position
like a refugee shelter or police station or park picnic table.

But some guys have gotten the rig into a semi-closely-fitting rigid enclosure,
which itself goes inside a frame pack, or is lashed to a bare pack frame.
(Not that you should operate an FT-857D inside a nearly-sealed box,
lest the radiator fins in back overheat).


The other guys can stop me if I'm wrong about any of this.
73's.
 
Yeah, I see a lot of go boxes out there. Today's hike was about an hour in because I stopped a lot to look for potential spots to operate, and maybe half an hour back out. That's the level of hiking I'll be doing with it, aside from when I can just park and setup at a picnic table. So that's why I'm looking at packs vs boxes. Obviously the boxes can offer a lot more protection, but I'm not trying to carry a suitcase up a mountain. The way I've been carrying it is the radio/mic go in one compartment, the battery and antenna go in the other compartment. Honestly it's not terrible if I don't need to pack/unpack quickly every time because the weather suddenly changed.

A few weeks back I made side plates for the 857 out of kydex. They're not as beefy as the fancy metal ones, but they offer some protection from the front and sides. They come forward and then curve out to access the headphone/mic ports and the Lock/VM buttons on the right. They're also work great to hang the mic. (That red wire doesn't plug into the mic, it's a 90 degree adapter for my headphones ;).)

1648336542739.png

Geez, I should dust that thing.

The second picture is taken from a high angle and looks like the left side plate doesn't cover the vol/RF gain knob, but it really does. You can see they extend forward beyond the controls.

1648336594108.png

So those side plates aren't perfect. I tried to make them out of plexi but the screws I had were either too short or way too long and the plexi was not interesting in countersinking. So I went with kydex which is significantly easier to work with and shape.

I read a lot of articles and watched a lot of videos on the end feds. Obsessively. Basically the conclusion I came to is that they are either: the best antenna in the world that works at every single frequency including 0Hz at 1:1.0 SWR in any configuration, or they are physically impossible. Being familiar with the internet, this is about what I expected.

I've seen a lot of guys running them as slopers (fed at bottom or top), inverted-V, inverted-L with great success so I figured why not. It was fun to build and learn about. Once built I hung it from a branch in the yard, hooked up the RigExpert, decided it was too long (surprise, I started out about 2' long just in case), so I folded it over on itself, taped it up, hoisted it back up and the SWR is dead nuts on 40, a little above where I want it on 20, and then the higher ends of 10 and 15. I know the meter on the radio isn't exactly calibrated lab equipment but it doesn't budge when I key the mic on any of those 4 bands. I'll run it as is for a bit and if I'm satisfied I'll trim it to final length.

I see the guys in that article added a balun to the enclosure, which is something I had considered. I've got more toroids I can use if I decide to add that. Right now I have a counterpoise but I also feed it with 30' of coax. I'll give that article a good read.

Interestingly when I had the RigExpert on it, I found the counterpoise made no change to SWR at 40/20 but flattened the low points considerably on 15 and 10. And it varied depending on whether it was under the radiating element, behind it, or to the side. I also found that raising the feed point a few feet also had some impacts. I took some notes but I was counting on the plots I took along the way and I guess I was supposed to save them manually. D'oh.

So far it's working quite well. I don't have a ton of run time because I got rained out both times. But a perfect example was a guy in upstate NY I could barely pick out of the noise at home, and shortly after in the woods with a homebrew antenna he sounded like a phone call.
 
The Bobs' antenna article is basically a design from first principles
(and they take you through the process that yielded the design).
You may find that you learn enough to modify anything sub-par in your current antenna
without having to start all over.

I'd have suggested the article if you were merely considering an end-fed half-wave.
Not looking to induce Builder's Remorse. It's sheer coincidence that
I learned about it recently.


The Kydex chaps are inventive, but half-measures will be ashes in your mouth
if you do bust a knob off - especially in the field.

However, I just thought of an expedient workaround:
  1. Separate the head unit.
  2. Wrap it in bubble wrap.
  3. Transport it in a modestly larger plastic jar.
Maybe the opaque green jar that Diamond nuts come in is a bit too narrow.
Lots of coffee cans are too wide and some too shallow.
But it won't take much picking through your recycle bin to find something
that allows enough bubble wrap to protect the face, but won't compress the wrap,
and is stiff enough to not get crushed in the pack.

Luckily, I don't recall any aspect of the head-separation design
which can't handle the number of unlatch/latch cycles
implied by the bother of taking a half-hour hike.
You're not going to do that more than a couple of dozen times per year tops, right?
In particular, no "molded latch hinges"
which could fail from being flexed too many times.
I'd feel rotten if I'd trolled you into cycling some tidbit
that fractured from overuse.


Don't be tempted to cram a lot of other stuff in the jar like the mic.
Be deliberate about protecting your investment.

I don't remember how my FT-857 was packed.
If there's a separate chunk or two of styrofoam
or vacu-formed plastic that perfectly fits the head unit,
you could just use that.


BTW, while I don't know if there are any buttmunch park rules
against stringing temporary radio antennas,
see if you can activate MountainSugarloaf Reservation.
Stone observation tower, trees, picnic tables, rest rooms (right?),
awesome views, road to the top if you're lazy...
A high fraction of all photographs of "Connecticut River Valley"
were taken from up there. It's a gem.
 
The Bobs' antenna article is basically a design from first principles
(and they take you through the process that yielded the design).
You may find that you learn enough to modify anything sub-par in your current antenna
without having to start all over.

I'd have suggested the article if you were merely considering an end-fed half-wave.
Not looking to induce Builder's Remorse. It's sheer coincidence that
I learned about it recently.


The Kydex chaps are inventive, but half-measures will be ashes in your mouth
if you do bust a knob off - especially in the field.

However, I just thought of an expedient workaround:
  1. Separate the head unit.
  2. Wrap it in bubble wrap.
  3. Transport it in a modestly larger plastic jar.
Maybe the opaque green jar that Diamond nuts come in is a bit too narrow.
Lots of coffee cans are too wide and some too shallow.
But it won't take much picking through your recycle bin to find something
that allows enough bubble wrap to protect the face, but won't compress the wrap,
and is stiff enough to not get crushed in the pack.

Luckily, I don't recall any aspect of the head-separation design
which can't handle the number of unlatch/latch cycles
implied by taking a half-hour hike. You're not going to do that
more than a couple of dozen times per year, right?
In particular, no "molded latch hinges"
which could fail from being flexed too many times.
I'd feel rotten if I'd trolled you into cycling some tidbit that fractured from
being used


Don't be tempted to cram a lot of other stuff in the jar like the mic.
Be deliberate about protecting your investment.

I don't remember how my FT-857 was packed.
If there's a separate chunk or two of styrofoam
or vacu-formed plastic that perfectly fits the head unit,
you could just use that.


BTW, while I don't know if there are any buttmunch park rules
against stringing temporary radio antennas,
see if you can activate Mount Sugarloaf Reservation.
Stone observation tower, trees, picnic tables, rest rooms (right?),
awesome views, road to the top if you're lazy...
 
QRPGuys make a bunch of EZ DIY antenna kits, as does Pacific Antenna. Worth a look. On eBay, you’ll find QRPGuys knock-off pre-assembled endfeds for <$25 shipped from China but there are a few US-stocking vendors that ship more quickly. Just attach a long wire to a winder and roll out as needed for any given frequency.

I’ve done some SOTA with my ICOM IC-705 and am kitting up a new backpack to hold that rig with IC-AH705 tuner, a Bioenno battery and various antennas. I’m just getting a DigiPi up and running craiger.org for digital work on a Raspberry Pi Zero W2. Using a smartphone or small tablet to connect to the DigiPi hotspot, I can run that “headless” - without a display or keyboard attached to the Pi. I’ve successfully run APRS, WSJT-X FT8 & WSPR and JS8CALL and am getting WinLink up and running too.

And the mike still work for voice! 😉
 
Nice. I built a "Shack in a Pi" last year and it worked okay but I was using a small screen and fitting what you need onto it was such a compromise you couldn't see anything. Add to it that I don't really understand what to do with the digital modes. I answered some CQs on JS8Call and the folks were clearly not looking to chat. For whatever reason I couldn't save my info, so when someone asked for everything (QTH, rig, antenna, power, software, etc) I had to type it manually, and they usually were on to the next person by then. I know you can set canned responses, which is what they're looking for, but then it's just their machine sending a canned request and my machine sending a canned response.

WSPR was cool to see how far I could get on so little power. I was really impressed with that.

I wanted to like the digital stuff, but I got so discouraged by fighting with software, settings, etc that I gave up. I bought a windows laptop to give it another go but haven't tried yet. I'm enjoying phone for now so at least I'm doing it.

I should give winlink another go. And SSTV would be cool. So we'll see.
 
I wanted to like the digital stuff, but I got so discouraged by fighting with software, settings, etc that I gave up.
(Haven't tried, but) judging from all the questions I'd see online, that'd be par for the course.



Oh, back in the day one there were half a dozen(*) FT-857/897 web "shrines" on Yahoo Groups
that were awesome compendia of documents and advice.
Stolen service manual PDFs, how-to photos of driving autotuners, all that good stuff.

Some stull will hopefully have been preserved elsewhere.
I'd hope there'd be a healthy community on Groups.IO or Google Groups,
but I haven't looked...

(*) It was easier for lids to create an entirely redundant discussion group
than to find the one(s) that already existed.
 
I’m just getting a DigiPi up and running craiger.org for digital work on a Raspberry Pi Zero W2.

Very interested to hear how you make out with this project, especially if there’s lots of programming, command line stuff, etc. involved. The inclusion of WinLink would be so nice especially if it’s not too klunky. Also, the 705 is a great radio, no? It’s a keeper for sure.
 
Very interested to hear how you make out with this project, especially if there’s lots of programming, command line stuff, etc. involved. The inclusion of WinLink would be so nice especially if it’s not too klunky. Also, the 705 is a great radio, no? It’s a keeper for sure.
I remember struggling a little bit with Winlink but I got it working, so it must have been easy. I have very little patience for figuring out software. I seem to remember that signing up for an account was the clunkiest part. You have to use it or lose it and I lost it, but it's probably a good idea to get it going again.

The software I used for the Pi was reasonably easy to setup (Build-a-Pi). I didn't write any code, just followed the directions. I think if you ran it to a tablet instead of the little 7" screen I was trying to use it would be better. That was actually the route I started down when I decided a laptop was cheaper/easier and already had a keyboard, touchpad, and battery. I don't know how it compares to anything else, but it appeared to be all inclusive.

Back to my original question about packing. One of my youstubes guys KB9VBR does a lot of POTA-ing with his 891 and uses these wraps. They're for camera equipment, which is particular about being banged around. I bet that along with the side protection I already made would provide adequate protection in a backpack pocket all by itself. Pro tip, the colors vary widely in price if you don't care about color.

I was up at my Super Secret Squirrel location today boiling maple syrup. I foolishly thought there'd be time left in the day to play radio. There wasn't. Just a glorious 8 hour day of standing next to a barrel stove in 23 degrees, constant wind, and snow. I don't know why I put myself through that shit.
 
(Haven't tried, but) judging from all the questions I'd see online, that'd be par for the course.



Oh, back in the day one there were half a dozen(*) FT-857/897 web "shrines" on Yahoo Groups
that were awesome compendia of documents and advice.
Stolen service manual PDFs, how-to photos of driving autotuners, all that good stuff.

Some stull will hopefully have been preserved elsewhere.
I'd hope there'd be a healthy community on Groups.IO or Google Groups,
but I haven't looked...

(*) It was easier for lids to create an entirely redundant discussion group
than to find the one(s) that already existed.
I found this bad boy. FT857D Operation Service
 
Back to my original question about packing. One of my youstubes guys KB9VBR does a lot of POTA-ing with his 891 and uses these wraps. They're for camera equipment, which is particular about being banged around. I bet that along with the side protection I already made would provide adequate protection in a backpack pocket all by itself.
Neil or Buzz broke off an ascent engine breaker knob
while bumbling around in the cabin on the moon.
They had to stick a pen tip into the hollow shaft stub to flip that bad boy.

What camera has had plastic shafts protruding a naked inch from a heavy box?

That breaker was probably better protected than the two small knobs on the -857D/897D.
Also the nested knob on the Alinco DM-330* series power supplies.
alo-dm-330mvt_oc_xl.jpg

I'd readily agree that H/T knobs can protrude a similar amount,
but they're sticking out of a smaller box
and may have an antenna protecting them to a modest degree.

If you mess with the bull, you'll get the horns...

That's what I'm talkin' 'bout. That's version EH007M90B from 2005.
I've seen EH007M90C from 2007.
I just discovered EH007M90D from 2009.
Don't know if there's newer editions. They're pirated, so...
 
I brought my (never been to space) radio on a hike today, and set up to try out my new 6m dipole. It worked beautifully. The band was shit though and nobody answered my call. :D

Then I took that down and strung up my end fed and decided to give 10w a shot. First contact was a guy in Serbia, then I got a guy on a DxPedition in Ireland. I got through a couple pileups mostly because of QRP at the end of my call, but whatever. I should really run QRP more often

I would have stayed out longer but it got cold, and my ass was killing me from sitting on a rock. I may cut off a slab of a yoga mat to bring to sit on next time. And it's time to tidy up my prototype end fed into a more compact package and upgrade the wire winder I made from cardboard. I'm starting to think I need a 3D printer.
 
I'm starting to think I need a 3D printer.
I was on the hunt for a set of spacers / bushings for a transportable HF vertical I've been building out with no luck unless I wanted to order them to my specs, kinda pricey. I ended up getting a 3D printer off of Amazon this weekend and have been playing around with it, yes, there is a learning curve. I am 100% confident that this will get me what I need plus other goodies and am looking forward to getting up to speed.
 
I was on the hunt for a set of spacers / bushings for a transportable HF vertical I've been building out with no luck unless I wanted to order them to my specs, kinda pricey. I ended up getting a 3D printer off of Amazon this weekend and have been playing around with it, yes, there is a learning curve. I am 100% confident that this will get me what I need plus other goodies and am looking forward to getting up to speed.
What did you get? I have so much crap at my house it's becoming borderline unlivable, so I'm really trying not to buy a 3D printer. But it would be handy for a lot of things.
 
I can't vouch for the fudge factors, but I used a 3Ah LiFePO4 battery with my FT-818 during Winter Field Day and got 6-7 hours of run time before the voltage started to drop. For LiFePO4s, that means the battery is just about out. This calculator pretty much matched that. I wouldn't take it as gospel, but if you are looking to ballpark a battery and don't know whether you need 9Ah or 100Ah, this should help.

 
I was just playing with the RF exposure calculator on ARRL's site and they have mode duty cycles. Those match up with the fudge factors used in the battery sizing spreadsheet I mentioned a few posts up. That gives some more credibility to it.

 
  1. Transport it in a modestly larger plastic jar.
Maybe the opaque green jar that Diamond nuts come in is a bit too narrow.
Lots of coffee cans are too wide and some too shallow.
But it won't take much picking through your recycle bin to find something
that allows enough bubble wrap to protect the face, but won't compress the wrap,
and is stiff enough to not get crushed in the pack.
plastic peanut butter jar?

and my ass was killing me from sitting on a rock. I may cut off a slab of a yoga mat to bring to sit on next time
Amazon product ASIN B000LC7Y42View: https://www.amazon.com/Northeast-Products-Heat-Seat-ThermaSeat/dp/B000LC7Y42/


Then I took that down and strung up my end fed and decided to give 10w a shot.
10W or 10M?
 
I would have stayed out longer but it got cold, and my ass was killing me from sitting on a rock.

A folding camping stool is what you seek. I use it when working in tight quarters for clients (think network closets), kids sports (awesome height with a monopod mounted camera and lens), and general camping sit downs when I'm away from the campsite.
 
A folding camping stool is what you seek. I use it when working in tight quarters for clients (think network closets), kids sports (awesome height with a monopod mounted camera and lens), and general camping sit downs when I'm away from the campsite.
I have a folding chair that's pretty small but it requires balancing. The modern ones have four legs but mine only has two and you provide the other two with your own legs, like a sucker. Are you talking about the three legged kind like this?

6c6caed7-e246-4e5f-8cb2-1b08d32a5f81.8c336d4009fece7e580743507803b02e.jpeg
 
I have a folding chair that's pretty small but it requires balancing. The modern ones have four legs but mine only has two and you provide the other two with your own legs, like a sucker. Are you talking about the three legged kind like this?

6c6caed7-e246-4e5f-8cb2-1b08d32a5f81.8c336d4009fece7e580743507803b02e.jpeg

Yup, that's the type. Tiny and light, can be strapped to your pack and you won't even know its there.
 
After this weekend's bullshit conditions, I figured I'd be gentle on the ionosphere and use my FT-818. Running 6w I worked a guy in the Dominican Republic, also running QRP, 1717 miles away. Not too bad for SSB.

I had a 20m inverted vee dipole strung up in a tree over to my hammock. Everything was quiet today. I was handing out generous 51 signal reports and the only guys who budged my S-meter were running legal limit. Fortunately the Super Secret Squirrel Location has a very low noise floor.

For such bad conditions, I still worked ND, AL, UT, TX, LA, FL, and of course DR. I couldn't get or hear anyone close.

I had to check, and the TX park was about 1895 miles away, dang. How is this stuff even possible?
 
I'll throw this in here because it's useful when portable and you don't have a list of beacons handy (who does?). I won't pretend I already knew this, but in this K4SWL video he uses the Colorado broadcasted atomic clock times to gauge propagation. Slick.

From NIST.gov: The station radiates 10 000 W on 5 MHz, 10 MHz, and 15 MHz; and 2500 W on 2.5 MHz and 20 MHz.


View: https://youtu.be/P2R3-VkRLqg?t=1892
 
I had a killer time portable on Saturday. I learned that working a pileup with a hand mic and laptop required a lot of transitions from the mic to the keyboard. I got progressively sloppier as I got cold. I told myself to cool it with the spending, but in a moment of cake-induced weakness I ordered a Heil BM-17 headset. I got the foot pedal, which I may or may not use in the field. I expect I'll want to use a headset at home, too, so the foot pedal may just live there and I might make a hand activated PTT. I'm not really sure how pressing a button on a PTT vs pressing a button on a hand mic is different, but people seem to really like them.

Mechanics aside, just having a headset is gonna be an improvement. The headphones' response is 100-5000Hz, so it should kill a lot of hiss and keep me from squinting at the radio to hear better. Plus it's yellow, so reverse tactical.

Now I'm looking at arcade buttons...
 
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