Attached all the external bits to CRX1, connected the straight key, headphones and antenna, and then applied power.
No smoke, no flames, huzzah! It works!
Put on the head phones and immediately heard the same whining noise that the CC1 I assembled was making. There was also no sidetone when I pressed down the straight key.
Crap. Failing at building things.
Fortunately Jason/NT7S and Thomas/LA3PNA happened to be around in the #etherkit IRC channel (irc.recursiv.com), and helped me do some troubleshooting. Ran through some simple tests with Thomas to verify that at least the sidetone, audio and muting sections were working. Added a jumper to JP2, which gave me a sidetone. Had I read the assembly docs closer, I'd have known that.
Jason provide voltages to look for on the transistors, so out came the DVM and I started poking around. Everything checked out ok, except I wasn't getting voltage readings in the VXO section. Duh, I needed to add a jumper to JP1, which I also would have known had I read the assembly docs closer.
Once I did that and applied power again, I started hearing some noise and also caught a small bit of CW in the background. Success! The whine was still there though.
Jason suggested the wall wart as the source of the whine. Apparently wall warts are notorious for being noisy like that. I'll need to make up a connector so I can use a battery or the radio power supply. Hopefully that will do the trick. Then I can go through the alignment process.
You know, this plastic parts bin could actually make kind of a neat container for CRX1. Punch a few holes for all the connectors/pots, and add some feet. That could work, right?
The wall wart is probably why the CC1 produced the same whine as well. I guess I'll have to clear some space on the bench for that big old Astron power supply.
Maybe I really can build things after all.
aa7ee
It sounds as if by building the CRX1 you actually got 2 projects to work, by making that discovery about the wall wart. I do hope that was the problem.
The Astron PSU should do the trick. Those big hulking power supplies have big transformers inside instead of switching circuits, so don't generate the same noise.
I have a few sealed lead acid batteries under my desk hooked up to a charger, which is on all the time, constantly keeping them topped up. It powers my K2 and any other QRP projects I happen to be working on.
You are now officially a builder. Congratulations!
Dave
AA7EE
Eugene Mah replied to comment from aa7ee
i hope so. I should find out tonight if switching power supplies will work. I wonder if a ferrite or two might help with the wall wart
Jason still has my CC1. Don't know if he's had time to do any troubleshooting with it.
That Astron power supply will take up a big hunk of workbench space, so i might have to figure out a different place to put it while still keeping it accessible.
Eugene Mah replied to comment from aa7ee
having a proper power supply rather than the wall wart definitely did the trick. CRX1 sounds pretty nice and I was able to hear a several CW signals pretty nicely