Thursday, December 31, 2009

Cushcraft A3s Pickup in Mini Cooper

Yesterday I went to pick up a used Cushcraft A3s from a ham who had replaced it after only a few months with a very nice SteppIr and had offered it for sale.  I was supposed to pick it up last week but I postponed it due to the large east coast snowstorm.  This is my only my 2nd 3 el tribander I have owned (well maybe 3rd counting one that never got put up).  The 1st one was a TA-33Jr that I bought used in NNJ about 1964 after I had had a license for about 2 years or so.  My very 1st beam was a 'ZL' special that had been given to me as a wood frame only.  I paid $25 for the TA-33Jr and it was in good condition.  This Cushcraft looks almost new and was only outside of the box since last March.  Tom N3ZC (see his SteppIr on also included a Balun for me to use and I hope to get this antenna up for a contest this season. 

I was suprised to find that the Antenna broke down to a small enough size to transport in our Mini Cooper! 

Drake Twins

Several years ago I picked up a set of Drake Twins and the Receiver seemed to work for a few month then developed an AGC/Muting problem where it was about 75% muted all the time and therefore would not receive signals.  This week I decided to try swapping out some tubes as I thought a tube might have become weak.  After swapping out V1, V4 and V5 the 1st RF and IF stages it seemed more like a mechanical problem so I started up with the tapping to try and isolate the problem.  With the bottom cover off I found a loose rivet on the RF gain pot.  Squeezing it with the heavy neadlenose 'fixed' this issure.  The speaker wire had broken loose from the MS4 Speaker so I removed the AC4 power supply and repaired this.  Now it was playing through the speaker.

After this success I decided it was a good time to finally unpack the transmitter and check out the power supply.  Everything seemed to light up and was even hearing the 'spotting' tone in the receiver but it sounded raspy with a bad tone like the power supply ......wait where is that smoke coming from ....holy....crap the AC4 looks like it is on fire.  White smoke was billiowing out of the power supply so I unplugged it and found the HV Capacitor was leaking smoking black goo out the bottom.

The Heath C-3 Condenser checker was fired up and the bottom taken off the AC4.

Heathkit V-7a Another piece of Heath Test Equipment

Another Christmas present from the 'barn', the vintage VTVM from Heath.  This unit was dusted off and seems to work.  I will need to build a set of test leads for a more complete test.  I thought the battery compartment would be bad but there was only iron oxide that just fell out!  The battery contacts look brand new.  When was the last time you saw a Burgess battery?  It's been a while!

From the Internet
A Burgess battery was a specialized dry cell battery that was marketed to professionals such as electronic engineers, and to companies and government departments that wanted to buy massive numbers of batteries.

The Burgess Battery Company was founded by Charles F. Burgess in 1917 at a plant in Madison, Wisconsin, and later moved to Freeport, Illinois. The company was in business for several decades, but by the 21st century, the company became a subsidiary of Honeywell, and had discontinued battery production, as the heavy metals in their battery formula were found to be too hazardous for the employees. Burgess made thousands of customized batteries during the 20th century for which there were no replacement.

Since he had used them in his experiments and previous jobs, Emmett Brown chose two oversized Burgess batteries as fresh replacement batteries for the walkie talkies that were originally bought in 1985A, in preparation for Marty's trip to 1885

Another good link of old radio Ads.  (scroll down for Burgess goes to the Artic)

Sunday, December 27, 2009

Christmas Cookies and Cannons

We had a White Christmas  for the first time in many years.  We all enjoyed a great feast of turkey, ham, veggies, and  a tray of homemade Christmas cookies. Not as many people as we had at Thanksgving but those who could came by and we had 10 or 11 for dinner both Christmas Eve and Christmas day.  Some of the boys shot 'flaming snowballs' out of the 'cannon' after dinner and in the dark.  I gave my nephews a copy of 'One Crazy Ride' and I got to watch this DVD which is the 2nd movie by the Indian Adventure rider and film maker Gaurav Jani and Dirt Track Productions  My radio related gift was a copy of F.A. Wilsons book "An Introduction to the Electromagnetic Wave" which is available used for about $5 and is a good treatment of how radio waves are propagated with out 'too much' math.

Wednesday, December 9, 2009

Open Hangar Day at Massey

Sunday PM was the Massey 'Open Hangar' party at the Air Museum. Trish and I have attended the last several years and this year the WX was good and there was a great turnout. Lots of planes to see. Every time I come year there are improvements to the facility and more to see. There is a great shop and a nice grass field with two runways. It is worth the stop if you are in the area.

Sunday, December 6, 2009

Clipperton L on ARRL 160 Contest

ARRL 160M Summary

1.8 122 Q's 247 Points 43 Sections 10,621 Score

After working fifty or so stations barefoot in the 160 contest yesterday evening. I decided to put the Clipperton back online for a while even though it still has the Ip at turn on issue. Wait though I do have that used capacitor board I wanted to try so I opened it up and changed the HV filter board. I had already checked all the caps with my Heathkit magic eye tester they were replaced onec from the original with nice (but still a bit old) Sprauge metal can 150uf 500V units. I checked all the resistors decided to leave them as they were all right on the money as far as I could tell with my meter. I pulled all the diodes as they looked original and replaced them with modern HV 1000v 60A high speed diodes that were on super sale at Allied so I bought 100 of them. They are made for switching power supplies and are not 5408's but look about the same and thought I'd try a set. I removed the 'equalization' by pass caps and left them out as someones paper suggests (Measures?)

While the unit was open I inspected the plate choke and found what looks like a previous hot spot on the side near the plate end where the insulation looked damaged on a few turns and the wire was loose too. Should this be rewound? What type of wire is it ? The wire has a whitish color to the insulation almost like fabric but I don't think it is. Or could the wire be 'tightned up' and revarnish to hold it down. Not sure this is the Ip at turn on problem but it looked suspicious to me.

The parasitic suppresser looked ok but are originals. I did get another used broken set of parasitic suppressor parts and anode clips so I can make some new ones at some point.

Also bought a vacuum relay off flea bay, an RJ1a (I think) to try in one of the Amps to get faster switching...

Was going to pull the two Chinese tubes I have in it now and put back in the two weaker originals to see if it is a tube causing the Ip at turn on but didn't this time.

Turned it on and did get a short 100ma Ip reading but then it was ok as before.

HV reads just a tad higher and the big difference seems to be that when switching from SSB (hi B+) to CW/Tune (lower B+) it takes much longer for the voltmeter to come down to the lower voltage. This change now takes maybe 3 sec or so where before with original caps it took maybe 1 sec or less. Both boards had the 'stock' bleeders. I am thinking this is due to the incrased total capacitance from the old original caps to somewhat newer and I think increase in value from 120-150uf.

This thing has 160m on the bandswitch but it really does not 'tune 160' in my opinion, it is however putting out 400 plus watts if you can keep it tuned up so I was able to get back on the contest and make a few more contacts with a bit more power. I really need to reread the 160m mods for this and do some of them. It really does not matter much where the knobs are on 160 so I just leave the Load and Tune on max cap and go.

The antenna is basically a 'rubber duck' for 160m, a Alpha Delta twin sloper thrown out the window of my 3rd floor shack and tied on to my hedgerow in the side yard. With this rig I did manage the west coast and a few VE's and Caribbean stations for 135 or so contacts.

Next week the Raytrack is going back online and the Clipperton will get opened up yet again for the Ip at turn on issue and maybe 160 tuning and possible QSK ...

In the meantime I am still reading...

Tuesday, December 1, 2009

3-500z's Pin Resoldering

Getting a good pair of tubes has been difficult. Two arrived broken from Canada. Today one more (out of a matched pair) arrived from OK broken and the other one looks to be knocked off center some. On a positive note two that I thought had bad filaments survived the CQ WW contest after having the all the pins cleaned with 80 grit sandpaper and resoldered. They are putting out a lot of power!