Hello,
So, I've bricked my FT-817 while trying to install a digital SSB filter
in it :-/ Not entirely sure what went wrong, most likely I accidentally
shorted the filter's intended input-voltage wire to the chassis - but
the upshot is that while the radio still turns on the text on the
display (NOT the backlight, i.e. it's unlikely to be a PLL issue)
blinks, neither RX nor TX works, and the voltage between TP1084 and
ground is in the order of 1.5V rather than the expected ~13V. All of
this with the radio powered from a 13.8 VDC PSU, by the way.
Anyway, having assumed I blew the power-on circuitry of the radio I
replaced Q1104 and then Q1100 - to no avail. Which made me wonder, what
if the problem is not with these two transistors but with the POW-ON
signal driving Q1100? Maybe I have simply measured it wrong but it seems
to me that Q1100 remains reverse-biased regardless of whether
front-panel power is on or off.
With that longish introduction aside - does anyone know what the POW-ON
voltage in a working FT-817 should be, or perhaps could someone measure
it (TP1029 under the wide ribbon cable, if I remember correctly) for me?
Unfortunately I haven't got any reference hardware at hand and I really
would rather not order a replacement front panel for ~150 EUR only to
find out the radio still doesn't work.
Many thanks in advance!
73,
--
Marek M0JUR
