At the beginning of this month, I gave a presentation on slow-scan television to our local club, which was followed by a "live demonstration" where we sent images between two notebook computers (one connected to an LCD projector so everyone could see) via 2 meter HTs.  

The presentation included numerous sample images, with examples of problems one can encounter on the air, as well as how good reception can be with good propagation.  The question/answer session that followed was almost as long as the presentation itself, and we seem to have stirred up a lot of local interest in SSTV, on both VHF and HF bands.  

SSTV can be worked with little more than a PC and a radio, using free software available on the Internet, making it a fun and accessible mode that everyone can enjoy.

-- Patrick Innes
   W4TQI
   Tallahassee, FL

Greetings to the forum!

Before I was HF licensed, I bought a Yaesu FRG-100b general coverage receiver.  This radio has been a good, reliable general-coverage receiver for many years, but its Achilles' heel has always been its lack of a keypad for direct frequency entry.

I would like to address this problem, but in order to do so, I need to find data on the CAT port and the data format used for remote control of the radio.  I suspect that this information is available somewhere in the FRG-100 manual, but unfortunately, mine has disappeared into a stack of boxes somewhere.  

If anyone has information on the pinout of the radio's CAT port (a 6-pin standard DIN socket, I believe), and/or information they could share about the CAT data format, I would greatly appreciate it.

Alternately, it is entirely possible that it would be less expensive in time, money, and effort to purchase an accessory keypad from a third-party manufacturer.  Unfortunately, I have not been able to locate information on such products.  As above, I would greatly appreciate any information anyone might be able to provide along these lines as well.

Thank you.

-- Patrick Innes
   W4TQI
   Tallahassee, FL

Greetings to the forum!

I recently received my first batch of QSL cards from the printer, and am ready to send out the first volley.  

The domestic cards are straightforward - my card with a nice note, QSL info, and a SASE are enclosed (and a slice of waxed paper to keep the SASE from sticking itself closed in transit).

I also have a small stack of cards for the outgoing bureau (Canada is considered to be DX too, right?), sorted according to the country of origin.

About the only question I have left is in regard to the half-dozen or so DX cards whose operators have requested that I QSL direct.  Looking over the previous postings on this topic, I have seen everything from sending IRCs to sending a pair of 'green stamps' to cover return postage.  I am aware that the postage situation changes from time to time - what seems to be the current "standard practice" for securing a response from direct DX contacts?

Anything else I missed?

Thanks!

-- Patrick
   W4TQI

Working in the digital modes a lot, my PC and radio must "play nice" with each other.  At first, I had difficulties with RFI from the PC, but with some tinkering, I was able to solve it to the point that my Icom now lives in a spot just six inches from my monitor, and only in rare circumstances do I have any problems with PC-based RFI anymore.

The main culprit turned out to be my monitor, a 19-inch CRT from Envision.  Although it has suppressors on its leads, I was still swamping my radio on most bands whenever the monitor was turned on.  The solution was to adjust my monitor's rescan rate.  

Before anyone yells at me, let me say that tinkering with a CRT's refresh rate can do physical damage to the monitor, particularly if you are using an older unit.  Find out what frequencies your hardware can support, and use only those frequencies listed.  

Adjusting your rescan rate on a PC is pretty easy - the adjustment lives in the same area of "display properties" where you adjust the color depth and screen resolution (right-click the desktop, and select the "settings" tab).  Its location from there varies with the video card's manufacturer, but is usually somewhere accessed by clicking the "advanced" button.

Finding the ideal selection takes some tinkering, and you may not find a setting that eliminates _all_ of the interference, since clearing up one frequency really just moves the RFI to somewhere else on the dial.  In my case, a setting of 85 hertz opened up almost all of the spectra where I usually hang out, with exception of 30 meters.  For that, I tweak it slightly to 75 hertz.

Again, your video card and monitor settings may vary considerably.  Read the documentation and find out which settings are safe before changing _anything_.  Otherwise, this could be an expensive lesson on cleaning up RFI from your PC.

-- Patrick
   W4TQI
   Tallahassee, FL

When I upgraded to General in March, I only had enough Morse to pass the test, no HF radio, and wasn't really sure if I would be able to afford one.  Some web-searching revealed a low-power PSK-31 kit for 20 meters from Small Wonder Labs, which was very reasonably priced.  Assembly is quick and easy, and there are only three toroids to wind, and one four-turn bifiliar transformer.  You can check out the assembly manual online to see if it is within your kit-building "comfort zone".  There is a little bit of a waiting list for shipment, but it isn't too long.

I operated QRP PSK on 20 meters for several months before I could afford a "big radio", and I still enjoy seeing how far I can go on just those 3 Watts of power.   PSK-31 is a very power-efficient mode, and using just an attic-mounted dipole oriented north-south, I have made contacts from Canada to the north, to Brazil to the south, and several contacts in Europe and Russia, as well as the western US off the sides of the dipole.

My PSK-20 is currently part of a project to build a portable PSK station, which should prove to be a lot of fun on the air.  I'm still working on bringing my Morse code up to snuff, but until then, CW isn't the only way to have fun with QRP!

(Note:  No affiliation with Small Wonder Labs - I'm just a satisfied customer.)

-- Patrick
   W4TQI

[ quote ]
the usual approach is to do all the audio shaping and filtering within your equipment.
  [ snip! ]
Nowdays with the superlative selectivity offered in the IF section of most receivers, additional audio selectivity is just simply not required.
[ /quote ]

I understand this, but a few dollars' worth of PVC pipe for a resonant speaker is more in line with my student's budget than a $170 filter module for my IC-718.  

Additionally, since the IC-718 only has one filter slot, when I _do_ decide to go for a filter module later, I can get an SSB unit, and further narrow the response with the speaker.

Thanks for the words of advice, though.

-- Patrick
   W4TQI

I am interested in constructing a resonant speaker for use with CW.  Unfortunately, all of the web pages I have found on the subject either require hard-to-find specialized parts for the resonant cavity, or have instructions which I have not been able to decipher.

If anyone has information on constructing one of these tuned speakers, I would greatly appreciate it if they could share them with me.

Thanks for your assistance.

-- Patrick
   W4TQI

Greetings to the forum!

I'm not sure if this is one for "homebrew" or "repairs & mods"...

I have a Midland Model 70-050C radio that's been re-tuned and re-PROMmed for use on 6 meters.
I've got a wiring harness for the Molex plug on the back, and the radio receives fine.
The front of the radio has a 4-pin mic socket; the pinout I have for it lists pin 1 (lower right) as 'audio in', pin 2 (upper right - common to case ground) as Ground/shield, pin 3 (upper left) as no connection, and pin 4 (lower left) as PTT.  Grounding pin 4 throws the radio into transmit as expected.  

My question relates to the 'audio in' aspect of pin 1.  What sort of signal is this pin looking for?  With no power available on the plug, am I looking at a dynamic mic input?  Electret with battery in the mic?  Anyone have any recommendations?  Caveats?  Manuals?

Thanks

-- Patrick
   W4TQI