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!
I now have a grounding rod, courtesy Becky's Landscaping Service, 650
Z100, PSK-20, wattmeter
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.
- I get a clean sine wave pair at 450mV when AF is not plugged in to
- With the PSK-20 off, when I plug in AF In but no antenna, it loses
about 10mv but remains clean.
- When I hook up the antenna, the AF In on the scope picks up some
- 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.
Leaving Terrace Hill, no QSOs on 20m PSK31 or CW or 40M CW.
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.
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
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
(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
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.
I am done with the PSK-20 and it at least makes noise. I haven't tried
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!
Board 2 (power supply) of the HFPacker
amp is done. Next up is
winding 13 toroids!