[Elecraft] 40M Tx Alignment Hi Current Concerns

[Don Brown]

Hi

Sounds like your power supply is dropping out. With the supply voltage down
to 10.8 volts the current will be high. The power supply should be steady at
13.8 to 14 volts. Some of the basic power supplies do not regulate very
well.

Another problem could be voltage drop in the power cable. Check the power
supply with a voltmeter at the supply terminals and hit tune. The supply
voltage should not change. The supply cable needs to be 18 or 20 gage wire
to keep the drop down.

Don Brown
KD5NDB

----- Original Message -----
From: "Gil Stacy" <gilstacy@hotmail.com>
To: <elecraft@mailman.qth.net>
Sent: Sunday, January 12, 2003 1:40 PM
Subject: [Elecraft] 40M Tx Alignment Hi Current Concerns


>
>
>
> I am attempting the 40M Transmitter alignment in K2 #3104 and have high
current concerns.  With the power dial set at 2.0 watts,  in TUNE mode, I
peaked L1 and L2 to 3.6 a max of 3.6 watts.
> I set the power dial to 5 watts, entered TUNE mode, and had a voltage drop
from 11.7 V to 10.8 with a current drain increase from .22 to 2.14 amps.
Recommended amps in TUNE mode are 1.3-1.6 amps.
> At 10 watts in TUNE mode, the voltage drop is 1 volt with a current drain
from .22 to 2.5 amps.  Reommended amps in TUNE mode are 1.8-2.0 amps.
> Voltage checks,  recommended value in parenthesis where differs from
actual reading.
> Q6  B ok, C 10.8 (13.3),  E  .27 (.4)
> Q7  B ok, C 11.16 (13.4), E ok
> Q10  S 1.5 (1.6), G ok, D 1.5 (1.6)
> Q11 all ok
>
> Q13  E ok, B ok, C  6.1 (7.5)
> Q20  S ok, G ok, D 31mv (0.0)
> Q24  G ok, S .81 (1.2), D .87 (1.3)
>  U9 1  ok,  2   4.8 (6.9),  3  5.02  (6.9),  4  31mv (0.0),  5  35mv
(0.0) ,  6  5.3  (6.9),  7  10.5  (13.8)
>  U10  ok
>  Q5 is untested as I have not pulled off the heat sink.Comments and
suggestions would be appreciated. Thanks.
> Gil KG4VCG