[Heathkit] DX-100 panel and info wanted

[Glen Zook]

Actually, if the loading capacitors were removed and replaced with a variable capacitor this was an "authorized" Heath modification.  In fact, they supplied a kit for this purpose.  Units that had this modification made were known "unofficially" as DX-100A units and that is one of the reasons that the next factory version was the DX-100B.

The two holes may be for two additional Heath modification kits.  The first was to add a spotting switch to both the DX-100 and DX-100B and the second was to add the AM/SSB switch when the DX-100 and DX-100B were used with the SB-10 SSB adapter.  The modification kit for the spotting switch also included parts to modify the keying of both transmitters to grid-block and to change the "shaping" of the CW signal.  However, this modification also changes the VFO so that it runs constantly when the transmitter is in the transmit position and thus precludes break-in (QSK) operation and for using the receiver as a keying monitor.

The other changes between the DX-100 and the DX-100B include the change from 4 crystal control positions (with the front panel switch) to a single crystal control position with the slide switch that has to be accessed by opening the top of the cabinet; the change to the "Apache" style cabinet; and there were 3 capacitor values changed in the driver stage to improve the grid drive on 10 meters (not much change but a little).  Also, the final loading was changed from the air variable with fixed loading capacitors in the DX-100 and the larger value air variable only in the DX-100B.  But, the loading capacitor change for the DX-100 came out before the DX-100B.

Glen, K9STH

Website:  http://k9sth.com


--- On Wed, 2/11/09, C E <catman351 at yahoo.com> wrote:

I just received a DX-100 modified to "B" configuration.  Looking for sites and any other sources for suggested mods.  Also, a former owner punched two extra holes in the panel.  If anyone has a wayward DX-100 panel in fair shape, I'm interested. Please contact me off the list.