Saturday, March 27, 2004 Zulu
I finished the main components of the HFPacker QRP Amp filter board. Now on to the bandsitch and cables, and then mechanical assembly, alignment, and (one hopes) first call!
- posted by Leigh @ 00:44 z 0 comments
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Wednesday, March 24, 2004 Zulu
Grounding Rod
I now have a grounding rod, courtesy Becky's Landscaping Service, 650 493 7060.
- posted by Leigh @ 02:28 z 0 comments
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Tuesday, March 23, 2004 Zulu
Z100, PSK-20, wattmeter
- posted by Leigh @ 20:42 z 0 comments
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450mV pp 1KHz from sound cardHooked to rig, no ant, no DChooked to rig with ant in, no DCTurns to 900mV pp when xmitting
The PSK-20 appears to work.

I had two problems: the output level of my sound card was too high, and I was that thinking that with only 1W out, shielded cable and ferrite beads was enough isolation, but I was wrong. I compounded the problem by a lack of shielding when I test-clipped a pot into the line for level reduction.

When I got the scope on the AF input I realized that the distortion happened exactly when the TX kicked in, and not coincidentally!

So I wrapped my test leads in aluminum foil, put in the 600ohm 1:1 isolation transformer in the AF Input line, and put in a biggeer ferrite wrapped multiple times, and the problem almost went away. It comes back if I hook up the AF Out line, so I will isolate it as well.

One remaining issue is that I do still see some scope fuzz on the AF In jack when I hook up the antenna to the PSK-20 and that fuzz is not present when the antenna is unhooked (this is with the no DC power supplied) but I believe that is a minor isssue.

Setup: Sound card output fed to 2K ohm pot outer and output taken from wiper and one side, then fed to 600Ohm 1:1 transformer, then to PSK-20 and scope, with ferrite bead at connector on PSK-20 side. 10MOhm scope probe. Modulation is at 1000Hz.

  1. I get a clean sine wave pair at 450mV when AF is not plugged in to PSK-20.
  2. With the PSK-20 off, when I plug in AF In but no antenna, it loses about 10mv but remains clean.
  3. When I hook up the antenna, the AF In on the scope picks up some high-frequency noise.
  4. When I apply power, the XMIT keys and produces 1 Watt, and the AF gets very odd and doubles to about 900mV. This effect goes almost all the way away when I put in an isolation transformer from Buxcomm and a multi-turn ferrite on the AF In.
Conclusion: I do need RF shielding and isolation between the PSK-20 and my computer.
- posted by Leigh @ 00:23 z
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Sunday, March 14, 2004 Zulu
Dipole in Trees in San Luis Obispo
out the windowbalundipoledipole in tree
I got the dipole strung up nicely but it isn't resonant on 20M and won't match. The Tenna Dipper says it is 50 Ohms at 16.6Mhz, but this low it won't be 50 Ohms at resonance. It looks so good, I hate to take it down, even though I can't xmit on it. Note: I later found that the SO-239 in my Z11 was flakey. I think I want to get an MFJ or Autek analyzer that gives me more data (resistance and reactance).
- posted by Leigh @ 18:12 z 0 comments
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Saturday, March 13, 2004 Zulu
Leaving Terrace Hill, no QSOs on 20m PSK31 or CW or 40M CW.
- posted by Leigh @ 01:30 z 0 comments
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Friday, March 12, 2004 Zulu
signPhoto 09Antennaradiothe hillfrom terrace hill

Terrace Hill, San Luis Obispo, CA, elevation 495ft / 144M Grid Square CM95qg.
- posted by Leigh @ 23:28 z 0 comments
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Tuesday, March 09, 2004 Zulu
I have the basics of my RPSK program working now. Using a modified version of gMFSK as the server and a simple Java program as the client, and netcat for transport over tcp/ip, I can remotely read PSK and display the waterfall, phase diagram, and character data. I haven't written the transmit/tuning side yet, but I want to make the receive side more integrated before I do, and probably integrate the network code into the clienr and server rather than using netcat. Then I can run the client as a Java applet.
- posted by Leigh @ 17:49 z 0 comments
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Saturday, March 06, 2004 Zulu
Photo 04dinkey
This is my FT-817 DinKey, which uses the '817's built-in keyer in the mic RR-45 connector. I ordered it from FSKarasek - KF6HQC. I had trouble figuring out how to get the DinKey into the Mic jack, and how to enable it once it was there, and sent mail after 6PM PST. Fred responded almost immediately!

Here is the info I got from Fred on how it works, with a few of my own additions.

If they DinKey just causes the VFO to move up and down, then MIC KEY is disabled. In the F-directory (push and hold for one second) menu item #36 is Mic key. this needs to be in the on position. Then in the regular quick-push F-button, BK in must be turned on and KYR must be on. (BK can be turned off to use the FT-817 as a code practice oscillator). Finally, uou must be in CW or CWR mode and with the VFO set to a ham band, even for CPO operation.

If the FT-817 starts sending dahs continuously as soon as you turn on KYR, then your straight key is plugged in and the shorting bar is on.

If the key is sending dits and dahs opposite from what you like then F-directory menu item #19 which is CW PADDLE can be switched to reversed or normal to suit your taste.

To install, the key does press in a bit on the hard side but is necessary to prevent the side to side movement which could damage the rj-45 socket or the key.

The sending speed and CW weight are menu item #21 and #22.

- posted by Leigh @ 02:55 z 0 comments
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Thursday, March 04, 2004 Zulu
PSK-20 TopPhoto 05
I am done with the PSK-20 and it at least makes noise. I haven't tried transmit yet. I finished it last night except I had lost the #4-40x1/4" nylon screw that holds in the fnial transistor and had to go to 3 stores before I found them at Fry's. Thanks Becky!
- posted by Leigh @ 19:53 z 0 comments
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Wednesday, March 03, 2004 Zulu
Board Two
Board 2 (power supply) of the HFPacker amp is done. Next up is winding 13 toroids!
- posted by Leigh @ 03:40 z 0 comments
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