Thursday, September 30, 2010

ZL Ham Launched Today 27th September 2010

ZL Ham Launched Today 27th September 2010

I am pleased to announce the launch of ZL Ham, New Zealand's Premier Radio & Electronic Interest Group. If radio or electronics is your thing, this is the place for you.

ZL Ham provides a number of collaborative features:

Share your news stories with back end syndication.
Keep others up to date with online blogging.
Add authoritative data to online wiki data bases.
Discuss and share your project on our online forums.
Files, personal journal, web links and much more.

Create an account and help drive ZL Ham!

After several weeks setup ZL Ham, New Zealand's Premier Radio & Electronic Interest Group, has been launched. ZL Ham is a community portal focused on all things radio and electronic. A place for New Zealand radio & electronic enthusiasts to share and publish. The web site has many different aspects and features. It is based around open source software packages which allow users to publish news and reviews, discuss their hobby and to announce upcoming events. Users can Blog, discuss issues on the ZL Ham forums, add items of interest to our radio wiki and yes, we even have an online shop coming soon. Enter your musings into your own personal journal and stay abreast of upcoming events with our online calendar. Create your own menu so that you can use ZL Ham as your home page. You will have to see it to believe how much has been packed into one web site.

So drop by and let me know how I can help your special interest group promote radio & electronics's in New Zealand, number eight wire and all. Rather than create what I think should be on the web site I encourage you to have your say. I have added news and other items to show members what the web site is capable of and I encourage members to help drive the site. If you are passionate about your hobby then join in. I will do my best to assist where needed. The rest is up to you. Many can relate to my story. At 12 I used to listen to the short wave radio. A little later I started to tinker with electronics. CB radio followed by Ham radio followed by a career in electronic servicing and computers. I followed my dreams and after more than 30 years I am still passionate about radio and electronics.

http://www.zlham.geek.nz

Full Article.

Help me rekindle that same dream with todays young people. Many are beginning to realize that the Internet, although great, just does not fill the same void as a serious hobby does. With so many aspects to radio & electronics there is something for those young people with drive and ambition. You to can enjoy the satisfaction of helping someone follow their dreams.

And you can not please all the people all the time...

This person thought he would respond to my invitation with this insult.

Graeme Nelson ZL2GDN

Hi Peter,

I just found your e-mail in my "Spam" folder, and ironically, it is spam.

That said, it is one of those rare spam e-mails that is of interest.

Also, I think you have mis-used the word "Premier" as your new group is neither the first nor the leading one (not yet, anyway).

TTFN.,
Graeme

Some people are born Lusers. Mr Nelson has been spanked more than once on the ZLHams Yahoo group for his Luser attitude.

Tuesday, May 25, 2010

G1000A Rotor

I have added two new connectors on the back of the controller. The extra connector will allow me to computer control the two rotors I have.

Neat and tidy with a few bits of heat shrink tube.


The G1000A only uses four wires to the rotor. The other terminal block allows six extra connections to a computer interface using a MC9S08QG8 micro.

Sunday, October 11, 2009

New Circuit Board.

The finished item. I use the Ferric Chloride solution cold so it takes about 4 hours to complete. A pot scrubber is used to clean the marking pen traces.

Art Work Complete.

Ready for etching.
Cost $32 for a doctors visit after several daily drawing sessions. The act of rubbling my elbow on the bench resulted in an inflamed and infected elbow.

Tuesday, September 8, 2009

Circuit Template

Another cardboard template and the resulting dot pattern. It is going to take a few days to hand draw this one.

Saturday, September 5, 2009

1296 Amp

Rack case and other bits for the amp. The case originally contained a power supply built to supply bias for UHF tube amps (20 odd volts cathode bias). Left meter. 30v/10mA scale. Right meter 25W (Will be x 10) power meter. I will have to counter sink the cavity a bit to line up with the front panel hole that originally had the meter switch.

Monday, July 20, 2009

1296 100W 2C39 Cavity

I got my hands on a cavity and 4 tubes. One of those round-to-it projects where a round-to-it was never found.

I could not put it in to storage until I confronted the main issue.
No cathode / heater socket / plug / mounting hardware.

Head first into the junk box and several hours of cutting, etching, fiddling, etc. etc and the challenge is solved.
Once I have the power supply built I can revisit the project and find the teflon sheet, glass trimmers and other odds and sods.

Top: The cathode and heater socket / plug assembly.

Middle: The tube chamber, 1KV BNC and N Type link coupling.

Bottom: Boxed up ready for storage

Etch Kit.

It can be a messy business etching boards. Ferric Chloride pallets can be added to hot water for a quick etch however I prefer to turn it into a solution to minimize waste. Small boards can be placed under a light to speed up the process however large boards can take one or two hours with cold solution.

I made two double sided boards for my 1296 cavity.

Monday, March 30, 2009

Mini Tower

This mini tower is 3 meters high. The pole that slides up the center is 5.8 meters long and fits just below the guide at 1.9 meters up. I think this was an old windmill tower and worth its weight in gold just for the two castings that make up the top plate and guide.

It was in poor condition with the legs rusted out at the top plate. I flipped the legs due to a bend in one which was less pronounced, after some bashing with a sledge hammer, at the top and cut about 100mm off each leg. I drilled all new holes and a full set of new galvanized bolts finished the hardware.

Then came a full paint job with "Galvit" galvanizing paint and a heavy layer of water based paint. Now I have to figure out how to get it up with a 5 element tri bander on it.

Thursday, March 12, 2009

70cm Preamp

Low Noise UHF Preamplifier.

The circuit is pretty standard fair, common emitter, bipolar and uses all surface mount apart from the inductors. All the caps are 0603. One 0805 resistor (base bias) and one 1206 resistor (collector current). The transistor used is a BFG67.

Power is supplied through a feed through capacitor mounted on the copper plate on the top side of the small box and sealed from the outside with wax.

The local engineer tapped the holes for the N connectors. The case has a neoprein seal and hopefully the whole thing will be moisture proof.

Friday, September 5, 2008

Power Supply Images.

(1) Still lots left to do.

(2) A closer look.

(3) Top level moved forward to show next layer.

(4) Back panel moved to reveal the four transformers.




Sunday, July 13, 2008

Ceramic switch

It has been bugging me for some time. I keep looking at other options on the web and auction sites. Time to settle the matter once and for all. I have two nice ceramic switches. They came out of a Collins millitary linear amp running two 4CX250F tubes and the switches were controlled by a motor. The problem is that the switch position is controlled by a third waffer therefor has no manual position indexing.

Without positive feedback the switch is next to useless to me and I know that making something to do the job is pretty tricky. 18 positions. The switch layout takes up 9 positions. It is a funny switch. It is designed for capacitive arrays. C1 & C2 with a powered rollor inductor making up a plate tank circuit.

It is ideal for what I want to do. I have a C1 of 230pf duel section and C2 of 1300pf. For 160m C1 needs to be around 400pf so the two sections in parallel should work. Switching out the other section for 40m and above. C2 needs to be 2200pf or more reducing to 1500pf for 80m.

So mounting an indexing mechanism was the task at hand. A search of my junk collection located a likely candidate. An old two position switch with a ball bearing in a spring mount. I prized the spring mount from the end of the switch and found it was made of two pieces of spring steel. A quick rustle around in my nuts & bolts bin located another ball bearing.

I mounted these on a piece of aluminum added two standoffs and a cam made of phonelic circuit board with 18 drilled indents topped off with another piece of aluminum. It worked pretty well but maybe I will make another cam as the indents are a bit deep.

The standoff spacers will allow the whole thing to be mounted front and back and the only thing left to do is to find some way of adding start & stop tabs at the right positions in the switches travel.

Monday, May 26, 2008

Five Over Five

Recently I have managed to aquire 2 TH5 DX antennas. The one in the foreground needs a new plastics kit and has suffered from electrolysis. As the saying goes... We can rebuild him. The one in the background (Traps boxed) has a new plastics kit and shows less signs of wear and tear. It is hard to say how old these antennas are but my guess is between 20 - 30 years old. The Thunderbird has a mighty fine reputation with countless stations using them to this day.

The plan is to put both of the TH5's on the tower below. One at 25 feet and the other at 50 feet. I have seen a couple of ideas for a matching network but I do not like either of them. I have a few ideas of my own that I may expand on later. It is going to take a few rainy day missions in the garage to clean them up. As with the TH3DX I have I will take to the TH5's with a wire brush (Brackets) and a poly pad (Pot scrourer). The TH5 has an average gain of 8.5db. Stacking a pair of them will add 3 - 4 db. Giving a total gain of around 12 db. Add 500 watts of RF and I will be one of the stronger stations in NZ on 20, 15 and 10 meters.

Saturday, March 15, 2008

Tower

I have been doing some 3D Solid modeling. I bought a 15 meter tower in 5 sections. I want to turn in to a tilt over crank up tower.

Friday, December 14, 2007

Rig & Me

Here are a couple of pictures of my rig etc. My radio shack is in the back of a 6x9m double garage and it gets a bit cold in the winter. At least it gets me out of the house. The shack is also set up with a large electronics work bench and a desk for my computers.

As you can see I am a no neck front row forward and a little over weight now days. Most certainly I have a no neck attitide when it comes to people I do not like.

Guess I got a lot of that from my father.

I spent a lot of time with dad, from about 7 years of age, in the bush hunting pigs and goats. Often he would put down the gun and wade in umongst the dogs and finish them off with a knife. I can remember many times pulling into the pub car park with a pig on the bonnet. A rasberry & lemonade for me and of course I would always be beaming from ear to ear after the buzz of the hunt.

Tuesday, November 6, 2007

Morse Key and Paddle

I am trying to learn morse code again. Back in the early 1980's I started to learn morse but gave it away. Now I am trying again. I have these two mounted on a base and after recent encouragement I have repaired the straight key. It had a lot of sideways play in the pivot and was somewhat erratic when used. I pulled it to bits and with a little filling and light tapping removed the play.

The two shown are a Galbraith GK-11 Paddle and a W.T. No 2 MKII straight key.

Both are classic morse keys and worth a lot more than the $11 I paid for them. Thanks Pete ZL2AUB for passing them on to me.

Saturday, March 24, 2007

Yellow Steel Box

I came across this interesting piece of information on the net thanks to sm5bsz. The interesting bit as far as I am concerned is the note about yellowish steel. I am using a box like this to mount the 4CX250B tubes in. I have other boxes that will be used in the project. It is good that I do not have to shield these boxes when used in RF gear. I think these boxes where used for microwave equipment.


Material Relative losses
Silver plating 0.96*X
Copper 1.00*X
Aluminium (pure) 1.25*X
Brass 1.87*X
Aluminium (worst case) 2.17*X
Steel 25*X or more


Steel with a yellowish surface treatment, common in electronics, has losses similar to brass. I do not know what this surface is, but it is easy to verify the dramatic reduction of losses that it gives.