My outfit for field QRV

日本語版はこちら(Japanese edition)

Here is my way to lighten and easy-to-prepair/use equipments for field-QRV in 30m/40m. I think QRP is good for my purpose.

Why 30m?

because... There's more stations in 40m and it's good if I have 50watt-rig. So my antenna is adapted to both.


I envy you in US because you have many QRP-rig makers in your country. There's no rigs have narrow filter in IF!, and for 30m too.
But internet helps us to import rigs made in foreign countries. I use OHR100 simply because it was lowest cost at that time. This rig is poor at QRM, but It hardly cause probrem in 30m.


Power Supply

I use junk battely from note PC. This capacity is 1.8Ah and OHR100 draws current 700-800mA. Considering CW's duty cicle (may be 50% with full-QSK) and from my experience, this battery keeps 4-6 hours.



GP doesn't take much places to build, but it has probrem to contact with domestic stations because of large skip zone. Furthermore, GP needs many radials so it isn't easy to prepare.

V dipole with fishing-rod may be good, but it is quite difficult to find rod(s) that is over 7meter and isn't made of carbon. I make with 5.2meter rod instead (and simply hang the rest of wires...2meter each) and tried to use, but it was caught by branches so often. Moreover it must not be expanded to 40m.

So I had given this antenna to JE5DTS "Masa" who QRV high-band mainly. He changed it to horizontal(normal) dipole (see below).

horizontal dipole

Finally, I'm using inverted-V dipole NOW. I made the stand (base) from pipe and Pole from fishing rod. Because This base is independent (self-stand) when I shorten rod, so it's easy to QSY (add or cut off wires). It doesn't stand under strong wind. But to deal with this probrem, I simply put something on the base (like below-right picture).

inverted-V dipolecloseup of base


Coax and balun

I use RG-58/U 9m with sort-a-balun. This is below-left, and below-right is inside of balun. I use FT-114#43 core with 5turn, but it's too large to use with 50watt (It can bear under kilowatt!). FT-82#43 is enough to use.

coax cable with baluninside of balun

Dataseet from "トロイダルコア活用百科 "(left Japanese means "Ferrite core encyclopedia")

+ Band +-- FT-114#43 --- FT-82#43 --- FT-50#43 --+
| 160m |  6turn,550w    7turn,250w    7turn, 65w |
|  80m |  5turn, 1kw    5turn,450w    5turn,125w |
|  40m |  3turn, 2kw    4turn,900w    4turn,250w |

+- wire diameter -+- max current --- max power -+
|      0.5mm      |     0.39A           7.7w    |
|      0.7mm      |     0.77A            30w    |
|      1.0mm      |     1.57A           123w    |
|      1.5mm      |     3.53A           625w    |

Notice: It is said the wire can bare x10 of power listed above under TX/RX intermittent environment.


Keyer and paddle

Bencher's JA1 paddle is very comfortable one so I use it in home-station. But it is heavy to carry. Therefore I bought MK-44 mini paddle from Whiterook products. This looks like a cheap toy, but it's fairly satisfactory to use (excludes requiring both of hand: one to use, and another to hold).

MK44 mini keyMK44 is so small (and toylike Hi)

And I put Tick in this paddle. TiCK is keyer chip made by Embedded Research and has these merit.

Embedded Research recommends to embed them into owner's favorite rig. And Whiterook products provides MK paddle with TiCK IC (names MK-64/64MB/64MS).

superTiCK inside!Another TiCK keyer (adapts to Plug&Play :-p)

Blue chipes are 0.1uF ceramic condenser. Pay attention to interference especially near high-Q antenna (longwire, magnetic roop and so on...). It's better to put condenser directory to dot/dash terminal than input of IC.

(1999-01-23) I replaced this TiCK1 with superTiCK.

Old TiCK had problem :If you use LED instead of piezo and when pushbutton was pushed, on/off of LED becomes reverse (key input makes it normal). It is solved in superTiCK, so I replaced piezo with LED. But it causes difficulties of inputting memory :-( .


Headphone and microphone

Hi-Fi headphone fitting to ears is untirering for long-time QRV and shut out noises from outside. I use foldable one.

Microphone....How to use it in 30m? :-)



Left 2 is wire-cutter and gus soldering iron. I don't take them NOW and I take other 9 items plus vinil tape, heat shurinking tube.

Upper from left: wire checker, dummy load, film case for reserve parts, small knife, Lower from left: cheap gas soldering iron (not useful...), nipper, lighter, keyholder-like driver and compass, solder.


How about the result?

Very good. All of bagagge weights only about 4kg.

QRP set


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