[Lowfer] Makeshift lowFER receiving antenna

[Jim]

> 1.  Are you using the short PC board antenna, the longer 100 mm PC antenna,
> or a longer real whip antenna with them?

I use a shorter CB whip on mine.

> 3.  Looking at the simple PC board I suspect you use "Manhattan ugly
> construction" for lands other then  +, ground, antenna, and output.

That's the way I built mine. I'm building my third right now and still not 
real happy with my pad layout. I think someone more artistic could probably 
do a better job than I have been able to.

> 4.  I would think a cheap way to run coax between the two boxes would be to
> use TV type RG-11U 75 ohm coax and make use of F connectors.  Have any of
> you made use of done this?  Would seem to me you could then use BNC or UHF
> connectors to your radio.

I do. I use to work in CATV, so I've got plenty of cable and F connectors. 
Also bought a bag of several hundred solder tab female F connectors at a 
hamfest for $1 a few years back. So F connectors are almost universally used 
on the receive side of my shack. (An the lowpower VHF side for that matter.)

One thing I found interesting was that I could feed the mini-whip through a 
two way splitter (which was marked for 5-750 MHz) and still have decent LF 
performance down to the bottom of the NDB band. Insertion loss might have 
been a bit over the 3 dB you see at higher frequencies, but the noise floor 
was still several s-units high. Was kind of slick being able to feed two 
receivers with the same antenna with gain to spare.

> Also, I just got a message back from Crystalonics regarding the CP-666 FET
> transistors.  They will sell them individually and told me I can call them
> and order such tomorrow.  They are $17.50 each plus $5.00 shipping.

I used a generic 50 cent JFET and a power transistor I scrounged off an old 
oscilloscope board. Performance dropped off above 10 MHz or so, but I think 
that was as much my wiring as my selection of components. Using a bit better 
parts this time around and will be interested in seeing if I can get it to 
work as well at the higher frequencies as at the lower. Somewhere between 10 
and 15 MHz is where my version of the mini-whip and my passive Butternut 
vertical "cross over" in terms of which performs best.

> I'll try my new FT-950 today and test for internal birdies.  The FT-890 has
> a lot of them.  Maybe I need to start thinking of a long wave converter to
> around 4 Mhz.  As I recall, I saw a construction article in QST magazine a
> few months ago on how to build one.

Jackson Harbor has a kit that's under $15 I think. I've got a converter, but 
the only problem is getting measurements as accurate as many people on the 
list make (to the Hz basically). I can get +/-2 Hz or so without the 
converter. With the converter you have to know the oscillator frequency to 
the Hz to get that kind of accuracy. It's possible, but I was always 
subtracting 3.999987 MHz or 4.000011 MHz or oddball number like that. With 
the active whip I had enough sensitivity at the lower frequencies to ditch 
the converter.

I've changed over to a Ten Tec RX320 now that Steve was nice enough to make 
the LF mod to for me and it works fine. But until I started using that I'd 
used a Yaesu FT-857 and a Kenwood 570.

73 de
Jim W4JBM

Receiver - Ten Tec RX320D
Antenna - Butternut Vertical (SW) and mini-whip (LF)
Location - Bowdon Junction, GA  USA (33.6581,-85.1249 EM73)

http://www.hamuniverse.com/w4jbm/

"With a soldering iron in one hand, a schematic in the other, and a puzzled 
look on his face..."

Working the world from the New Dog Iron Ranch!