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!

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

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.

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.

Halloween

Happy Halloween!

Today I removed some Dead power diodes from the Raytrack P/S Yes when the interlock is closed the HV is shorted! 6 of 10 HV Rectifier Diodes are now shorted as well! Ordered some new ones from Allied because I do not think the ones that Radio Shack has are suitable, (they used to have some that were). The other Amps I have also been working on have interlocks that are in series with the on-off switch. Oh Well I should probably change these diodes anyway the ones in the boards look like they were changed once since mfg but this would still put them at least 20 years ago which is how long I have had the 1969 Raytrack DX2000L. I had purchased a couple of used tubes (I dont really suggest this) and was testing them for possible use in the amp which uses a pair of 3-500z's. One of the tubes was good and I matched it with another one for a fairly well matched pair. The B+ resistors smoked and the diode string just quietly shorted out!

CQ WW SSB Weekend at Lovettsville, VA

CQ World Wide SSB Contest was Oct 24 and 25th this year. The same weekend as The Fiber Festival in nearby Berryville. I decided to make it a portable operation.

Rig FT-990

Audio .WAV files from Audacity and RS comp Mic

Ant OCF 150' with 4:1 Voltage Balun

Log setup Acer Ferrari running N1MM

Single Op Low Pwr Assisted ALL Band

Band QSOs Pts Cty ZN
1.8 1 0 1 1
3.5 19 41 8 5
7 24 65 17 7
14 112 304 63 17
21 119 338 56 15
Total 275 748 145 45

Best DX New Zealand on 40M

Battery Tender Plus

Battery Tender Plus www.batterytender.com that I use on the motorcycle, airplane and QRP batteries died while in use at the airport. After drilling the rivets out of the case and putting the meter to it the power transformer was found to have an open secondary. Last weekend I was able to attend the Berryville, VA Hamfest www.svarc.us/hamfest and purchased a replacement transformer # 241-6-20 from this sheet www.signaltransformer.com/data/datasheets/241. The unit seems to be working correctly with this transformer installed. Cost for repair was $5. The original transformer was 1.25 amps and this one is 1.5A so maybe it will last for a while. The Dual Primary transformer allows for 115/230VAC operation and you need to jumper the primary appropriately. Parallel for 115 and series for 230 volt operation. Several small battery chargers that I have used over the years have failed and in three cases it was the transformer. Radio Shack also sells one that worked in another small 12V gel cell charger for about $10 now.