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 http://www.dirttrackproductions.com/.  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.








http://www.masseyaero.org/index.html

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!

Monday, November 30, 2009

CQ WW CW Contest

CQ WW CW Summary for K3PG

Operating Conditions

Antenna Cushcraft R-7 Vertical
Radio FT-1000MP Mk V
Extras
N1MM logger with DM780 running in the background as CW 'helper'
WinKeyer USB from K1EL
1969 Raytrack DX2000L (2 x 3-500z's)
Dentron MT-3000A tuner when needed
Alpha Delta Sloper for 160M
Desktop computer Celeron running Vista Home Basic
Vibroplex Code Warrior for manual sending
Koss K6 Headphones (for not waking others)
MFJ-259B for helping to tune the tuner
Heath Cantenna
MFJ 1700C Antenna/Transmitter switch
Drake W-4 wattmeter
Ott Lite Mdl T48086 (small portable folding desk lamp)
Weller WLC 100 (for repairing the CAT wire when the dog gets tangled up in it during the 'test)

N1MM Summary
Band QSOs Pts Cty ZN
1.8 1 2 1 1
3.5 18 40 10 5
7 175 481 78 24
14 186 527 82 23
21 64 173 42 13
28 7 17 6 5
Total 451 1240 219 71

Wednesday, November 4, 2009

Raytrack HV Diodes




Last week while testing some 3-500z's for use in the Raytrack I (by mistake) burned out 6 of the 12 HV Rectifier Diodes in the power supply. I ordered some new ones from Allied and got a heftier size 1N5408's. Here is a picture showing one of the two power supply boards (both are the same) You can see one of the old diodes laying on the board and the new larger ones installed.

Monday, November 2, 2009

Using a MFJ-259B to verify tuning on VHF Arrow Antenna




Recently I purchased a used MFJ-259B and although it seemed to be working well I could not get it to power up using an external source. The power was not getting past the DC connector to the rest of the circuit! I looked at the schematic and added a small jumper to connect the center pin of the power jack to the + on the board the same place that the battery power comes in. Yesterday I had tuned the 'Arrow' ant using a Bidirectional RF Wattmeter (old Heath IM-4190) and it seemed to be hearing better especially on UHF. This shows the VHF side with favorable SWR and I can now hear the low orbit sats on both VHF and UHF.