[MAMS] Central States VHF conference

[Dr. Gerald N. Johnson]

On 7/22/2012 2:13 PM, Zack Widup wrote:
> Interesting. I like that graph of the elevations for RAGBRAI that show
> it is generally trending downhill over the duration. That must've
> taken a lot of planning.

Some years they have encountered rises that cause most to walk up. In 
Iowa what we have for mountains I say are upside down. 200 or 300' feet 
deep river valleys only a mile or two across.

Their planning involves both the profile and the towns interested in 
hosting pass throughs and overnight stops. Not all are up to the task, 
and some counties won't allow them at all. And most towns aren't ready 
for a repeat next year.
>
> I suppose I can take the direct route to get there late Thursday
> afternoon and then take the scenic route home on Sunday morning after
> the "parting shots." It appears Saturday is the last day for RAGBRAI.

I expect they will still be leaving Clinton Sunday morning. I'd be more 
inclined to drive over to the quad cities, then take the river road one 
side or the other for a while then go east to where I74 breaks from 
south to south east if I was going to take interstates at all.

I don't detect any significant CSVHF activity on Thursday other than 
visiting which is important but not always in the program. I learned 
years ago as a long term radio club president that business meetings 
were tolerated, programs were accepted if entertaining and slightly 
instructive to the club population, but the prime reason for gathering 
was to visit. There will be much of that at CSVHF too, I recall we have 
had great chats in the hospitality suite in past years. And there will 
be a dull roar of conversations around the antenna range on Friday 
morning. Not all about antennas.
>
> I wasn't quite ready for a presentation this year. Maybe next time.
> Brian WA1ZMS wanted to do sort of a joint presentation with me at MUD
> this year, with me covering my construction project for 47 GHz and him
> covering 78 GHz. I think as things stand now that I'll be unable to
> attend MUD. I wish they had it closer to this part of the country.

I'll probably submit papers for the proceedings but it is a long ways to 
go. I got more inspiration yesterday for one on SMA connectors, the good 
and the junk. I hooked up a directional coupler to tune up that antenna 
and wanted and elbow. The first one out of the shoe box showed 3 dB 
return loss with a decent termination on the other end. Without the 
elbow, that termination was closer to 20 dB return loss. That elbow I 
think I'll put on the mill and section it to see what size spring they 
used to turn the corner.
>
> I haven't received My Softrock Ensemble VHF receiver yet. I'm curious
> if the kit involves soldering SMT packages with more than 16 pins at
> very close spacing. I don't have a problem with that; I've soldered
> EPM3064 chips with 44 pins before. But most of my surface-mount
> construction projects only use 1206 or 0804 chips and a few 3-pin
> SOT-23 transistors plus a few SMT trimmer capacitors and resistors
> that are fairly easy to solder.

I'm working on SoftRock Lite II for HF. I bought a couple kits for 
practice, there are 7 surface mount caps and three surface mount ICs, 
the divider, dual op amp, and the mixer. All else is conventional 
through hole. But there are 9 1206 caps in the BOM. Maybe some spares. 
Last night I printed off 43 sheets of instructions for assembly and 
test, double sided. There are some web pages on that which I downloaded 
last year. Probably the same on your kit, there's NOTHING but parts in 
the kits.
>
> I think K3SIW and K9PW have 3-foot dishes that they used in the 10 GHz
> contest last year. They are mounted on tripods so they are fairly easy
> to set up but not mounted on the car itself like W9SNR has done.

I dream of a truck topper or car ski rack mounted dish with manual 
aiming for a lot quicker setup. Last year my back was aching after a day 
lifing my heavy duty camera tripod in and out of the hatchback with 18" 
dish, and rig all in one. It was fast set up but the cantilevering it 
took to get it in and out got noticeable.

The experienced rovers say 18" produces pretty good gain (31 dBi) and 
with a 5 degree beamwidth, aiming isn't impossibly critical. Last year 
at CSVHF N5AC proposed using servos to make for easier slow motion 
aiming on a larger dish. A 30" dish ought to be nearly 5 dB better than 
an 18" dish and that can help when running low power on a long path. 
I've been searching out Iowa locations for a NLRS rove in central Iowa 
for Septemnber and some Gary thinks might be a hair long for the 2 watt 
stations. But until I get that pa running,l borrowed, or acquired my PA 
is only 100 mw and thats below the noise on some 200 mile paths even at 
CW and I've not been able to send slow. I can't send fast with a keyer 
but I can get it a lot slower than a straight key.
>
> I'm hoping to pick up more tips in Rover Row and the Dish Bowl. It's
> always great to see how others have assembled their microwave
> stations.

One of my papers justifies the close spacing rovers often use for the 
yagi stacks. I'll probably open with it. Another shows ways of 
underfeeding a dish to reduce its gain and increase its beamwidth for 
easier aiming.
>
> 73, Zack W9SZ
>
73, Jerry, K0CQ