Hi all. I just did the transmit testing for 40m in the third testing
stage on the RF board this morning. However, I ran into some odd
things. At 5 watts, the K2's meter reads 6 watts and the current used
is about 0.06 amps high. That didn't seem too bad (something to look
into) so I kept going. I set the power control for 10 watts and
tested. Now it's a full 1/2 amp high (needs 2.5 amps). I double
checked this with my DMM to see if the K2's reading was off, it
wasn't. Now it has the full set of UnPCBs in it, and I can hear
things on receive, and receive current is good at 220mA or so.
So I went to troubleshooting and did all the voltage checks that were
not transmit (I figured I would do that second). Here are the
results, with the major oddities flagged:
D1-D7: When it should be 7.5v, I'm getting 7.2v When it should be 8v,
I'm getting 7.9v. 0v is all fine.
Q2 is pretty close at 0.02v, 7.9v, 9v
Q12 is 0.07v, 6v, 0v
Q16 is 0v, 0.55v, 2.18v
Q17 is 0v, 2.18v, 2.97v
As you can see, those are all pretty close. But now things get odd. I
forgot to write down which was which, so I can only give them as
triplets.
Q18's three readings are 8v, 0v, and 2.2v. (Manual says 6.3v, -1v,
and 2-3v)
Q19's three readings are -1.39v, 2.3v, and 0v. (Should be 0v, 0.8v,
and 8v)
Q21's readings are 13.1v, 0v, 0v which is really off. (Should be
13.2v, 2.3v, 1.6v)
Q22 is pretty good at 1.25v, 1.95v, 12.09v.
Q23 is good also at 0v, 0v, 7.9v.
Now onto the ICs. There are some very odd readings here too.
U1 pins 9 and 10 both read a solid 0v when they should have small
numbers. The rest of the pins are all fine.
U2 is functioning correctly, as is U3.
U4 pin 7 is 4.93v when it should be 0v, and pin 8 is 0v when it
should be 0.1v. The rest of the readings are in line with the manual.
U5 has some issues as well. Pin 1 is almost 5v, not 0; but pin 2 is
0v not 5. The rest of the pins are fine.
U6 is fine, as are U8 and U11.
U12 is within 0.2v on all non-zero pins except pin 8 which is off by
0.5v.
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com
Locked
