[AMRadio] HT40MK1

[CL in NC]

Does anyone on here know details about the difference between Halli HT40 and HT40MK1 transmitters?  ER ran a couple articles a few years ago from Phil Legate about improving the HT40, and I did email him but not sure if he knows anything about the MK1.  The MK1 had changes to the oscillator and modulator, and included a mod indicator on the front panel, but no one seems to know if Halli fixed the spectrum issues with its changed oscillator section.  The 'Wireless Girl' online just did a rehash of Phil's info and warnings, but nothing new.  I have an HT40 I picked up over a year ago, but it was heavily modified in the osc/driver section with the 6CX8 being replaced by a 6CL6, everything was changed, so wanting to go back to original, but one with a clean spectrum and  on first look, the MK1 schematic may be the way to go.  If you have an HT40 schematic, and it has a pair of series connected neons printed on the schematic between the modulator and PS, it is a MK1, the latest version.

Charlie, W4MEC in NC