HW-101 Low Output on 40M and 6.8MHz Trap Adjustment

[Will, Mark]

Ken,

I wouldn't exactly consider myself an HW-101 expert but I do have an HW-101
and have been through some of the same problems.  Through my experience, I
found that the problem is usually in one of three areas.  I am assuming that
you have verified that you have a properly tuned antenna or you are tuning
into a correct 50 ohm dummy load.

1)  Grounding within the cage that houses the heterodyne, switch, and driver
boards.  This is the one that contains all of the tuning slugs for each
band.  You will probably find that, when the cover for these boards is
removed,
your RF output increases dramatically.  Don't be fooled by this, it is
probably because, without the RF shield in place, these boards go into
self-oscillation.  Heathkit put out a service bulletin explaining a method
of properly grounding all of these boards.  I think the Heath bulletins were
HW-101-4 and HW-101-8.  I found this to help, some...

2)  It is possible for the heterodyne crystals to drift off frequency after
some age.  I have seen some procedure described on this list which involves
inserting a trim cap with the crystal to bring the crystal near its proper
frequency.  You will need an accurate frequency counter to verify this.

3)  Another possibility that was given by a member of this list is:
It is possible that the tuning slug that is located just left of the VFO
(T1 or L1??) is tuned to an incorrect peak.  While aligning the HW-101,
there may be more than one peak while tuning this slug, one of them will
be much higher than the others.  Simply tune the slug past the first peak
and see if another, higher output peak, occurs.

I think the behavior that you are seeing with the mic/CW level control is
normal.

Hope you have success!!!

Mark C. Will
Drive Integration
LSI Logic Storage Systems, Inc.
3718 N. Rock Road
Wichita, Kansas 67212
Phone (316) 636-8088  FAX (316) 636-8889
<mailto:mark.will at LSIL.com>


-----Original Message-----
From: Ken Winterling [mailto:winterlingk at MBUSA.COM]
Sent: Tuesday, January 15, 2002 2:43 PM
Subject: HW-101 Low Output on 40M and 6.8MHz Trap Adjustment


HW-101 experts,

I need your help. I recently received a HW-101 in very good condition but
it has low output but only on 40M. It puts out 100+ W on 80M and 20M. Also,
turning the MIC/CW level control clockwise will increase the output until
approximately the 2 or 3 o'clock position. Continuing to turn the control
clockwise from that point causes the output to drop.

Another item of concern is the 6.8MHz trap. The manual states that it is
sealed and should not be turned. Mine is not sealed and I suspect it has
been turned. What is the correct method of adjusting this trap?

73 and thanks for any help.

Ken, WA2LBI

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