Low budget helping hand PCB stand

One little and simple "project"

The photo speaks for itself...
The design could be improved but more than 15 years of electronics soldering without "helping hands" there's no point for now :)

The "hand" come from some design store and was really cheap.

Grig

After making the pc programing interface for the TH-F7E I remembered to test against Linux in my Feodra Core 6 box before upgrading to FC10. I remember having tested the USB to Serial cable and not working with my TM-D700 in TNC mode.

Connected the cable to the Kenwood and to the USB plug an called "grig".... nothing.... tested again but powering on the radio after the usb cable, voila.... the bloody thing works... here is the command line "grig -m 220 -r /dev/ttyUSB0 -d 2"

"-m 220" is for model 220 wich is the Kenwood TH-F77, you can list like this:

"....[root@work2 ~]# grig -l | grep -i th

***MEMORY-WARNING***: grig[26426]: GSlice: g_thread_init() must be called before all other GLib functions; memory corruption due to late invocation of g_thread_init() has been detected; this program is likely to crash, leak or unexpectedly abort soon...
217 Kenwood TH-D7A 0.2 Alpha
220 Kenwood TH-F7E 0.2 Alpha
223 Kenwood TH-G71 0.2 Beta ..."

"/dev/ttyUSB0" is the interface created when connecting the usb to serial cable.

"-d 2" is debug level and my version is "grig 0.7.2"

At the moment funcionality is basic but it works, probably with new version of hamlib it could make something else.

My idea was to put the TH-F7 as an scanner connected to the computer to receive some unatended digital modes but I forgot the the audio ouput is used when connected to the computer.... dam!!!

PC programming cable for Kenwood TH-F7E

No big magic here, copy the schematic from the net, make an nice _expensive_ box and "voila": an programing cable for my TH-F7E.
Components were from the junk box and some from my local suplier, I think total cost even from an expensive supplier would be around 10 Eur/USD top most. Cost from Ken-timber(wood) is around 62 Eur, software is free of charge which is nice!

By the way the box is from "Vimeiro" spkarkling water. I have an antenna pre-amplifier inside another water botle in the roof :)
The plugs have to be grinded (trimed) to fit ( full entering) in the radio.



The board was from an power supply experimenting and as always a mix of "Manhattan style" and "Dead bug" which one is faster...

The interface schematic comes from: http://www.geocities.com/azkoza/projects/pg4p/g71cable.html

Here it is the schematic from the above site:












Incidently today as of writing I found another schematic that I didn't tested and dependes on an max232 to make level convertions. Is here: http://www.g1ivg.com/ken_thf7e.htm

Only had an small problem but was on the software side, winblows creates "com port 10" and I was expecting 3 so no communication at the begining.

About the radio: so far so good, easy to learn, a little deaf with the stock antenna ( read: dummy load), no small step on 446Mhz to listen exactly on PMR frequency.

In Linux I still haven't tested the interface because the USB to serial cable is not fully operational, I will upgrade soon to Fedora Core 10 and test then, in FC4 and 6 it didn't worked, I have reception but no transmit. Chipset for the cable is PL2303.

What's up

Busy busy busy.... but still some time to solder...

Pretty much I've been doing some small things:

- Aircraft band receiver (done but partiatly working)
From: http://py2ohh.qrp-br.net/trx/corujinhavhf/corujinhavhf.htm

- Kenwood TH-F7E programing interface (done and working)
From: http://www.geocities.com/azkoza/projects/pg4p/g71cable.html

- Frequency counter from an Chinese store radio (done/broke, done another broke another by static)
From: Chinese store ( also similar do Pound Shop Radio )

- FM receiver (done, working in box but no power is connected to :)
From: An kit laying around in the shack :)

- Loop antenna for MW/SW (done, works, could be improved)
From: Mixed design from web and some experimenting (read: from parts laying around an UTP cable)

- New box for the PSK interface (done, lost 2 screws from the 4 that close the box)
From: Old telecom box

Will post some photos and articles as soon as I find the cable to transfer the images from the camera :)

Other interesting things:

My oscilloscope broke, "caboom", crashed, exploded... I'm trying to fix the bloody thing...
Well it's an advantage, now I have to test things with other methods and learn something new :)

My HF antenna ( some people disagree on what that object is ) broke; well it was make to broke at some point in time, it's just an piece of wire in dipole shape more or less cut'd to the 17m band, hanging on shoe strings between to chemnis pointed est/west... But permit's me to make some nice qso's with only 100w geting over some of those killowat pileup busters that make more electromagnetic noise than an microwave oven! ( you know who I am talking about :)

The QFH (Quadrifilar Helix) antenna

...Another day, another antenna.
For an long time I was wanting to receive weather images from satellites but lack of time had placed in standby my desire.

After getting the first images with the Kenwood TM-D700 it was time to get an dedicated receiver. Checking the available options including building one I opted buying one from Miroslav (OK2UGS) at his website http://www.emgo.cz/
"Miro" was at the Ham fair in Germany so it took some more time to send me the receiver but as an compensation he sent me one pcb board for an DRM receiver (I have now another project in standby, hi)
After completion of the receiver (was a matter of putting it on an box, it come allready built).



I decided to make some tests with different antenna designs I saw at the web. Soom I arrived the conclusion the for the right job the right tool so on to make an QFH antenna.
The best (best relation between instructions/cost/easiness of construction) design I saw was the one at:
http://www.g4ilo.com/qfh.html although for a total understanding of connections the schema at http://www.pedrolo.com/satelites/antena.html is more clear (he has an nice use for some ready available materials, hi)

The antenna was build with ready available materials ;electricity tube VD16 and VD32, RG58 cable and electrical isolation tape and some more self amalgam tape. Total cost was around 15 Eur I think, excluding my time :)
The dimensions you can get from the above sites and the images are bellow.
I am quite satisfied with the image quality but still trying to improve. I use wxtoming software running in Linux. Please read the wxtoimg FAQ if you are not getting nice quality (I had some problems by not reading the FAQ).
At the moment I am putting the images received at: http://www.ttbike.com/site/ct2gqv/images/

The antenna during build process.

Some measurement:



And this is my "radio" horizon from South (left side of image) to North (right side of image).

73 de CT2GQV

p.s. Are you an English native? Probably you can correct my lousy English, we are allways learning so all comments are welcome!

The SWR meter (one of)

After making the SWR meter for the antenna tuner I am building I decided to finish another one that I never put to work due the low acuracy.
It was based on an design I saw on the net but works lousy for the low bands so i decided to use the box and some internal parts and build a new swr meter based on this design. My design isn't exactly the same except the main parts (torroids and basic schematic), my microamp meter connects directly to the REF/FWD switch and I also bypassed the choke coils.

Here is another view:

First APT weather satellite image!

I am waiting for an dedicated weather satellite receiver, meanwhile I decide to test the waters with the trusty TM-D700 and one of the home made vhf vertical antenna.
After installing the software (wxtoimg) in the dedicated to radio Linux computer (I only use Linux) and after updating the keppler elements the next satellite pass was in an hour, so nothing like wait for the transmission (I still remember the first time I listened to an amateur satellite).

Honestly I was expecting an worst image due to the antenna/radio setup.

Here is the antenna (you can call it any other thing) and the first image: