On 01/08/2014 01:36 PM, Charlie Cunningham wrote:
Hi, Bill
I was also going to ask if you have a choke input filter -or if you could
change the PS filter configuration to choke input to help a bit with the HV.
Also, check your line voltage - especially at night when the load on the
electric grid drops. I've seen my 240 VAC here get up well past 265 volts
at night! Use a trusted, well calibrated volt meter and take some voltage
readings at different times of day to get a feel for what the line
regulation looks like! Note that a 10 % increase in line voltage would
increase that HV from 825 VDC to over 900 VDC. 10 % high line is not
really unusual. Finally, you can check with your local PUC - there are
regulatory limits to how much the AC line is permitted to vary - but I'd
start with the power provider first. Maybe they need to drop your
distribution feeder down a tap at the substation. Excessive voltage is hard
on lots of things around your house besides DX-100s! The utility can cme out
and put a recording voltmeter on your line for a while to see what's going
on, if you complain about excessive line voltage.
GL!
73,
Charlie, K4OTV
Hi Charlie,
The DX-100 High voltage is choke input by design. I changed the low
voltage supply to choke input as well and the rf stages are behaving
very nicely with that. I already think my line is "high" and I'll take
readings various times as you have suggested. Light bulbs don't seem to
last very long here, either.
Tom asked about bleeder current. I didn't try to measure it but I
watched the high voltage decay to zero in a very few seconds when I
switched it off with no 6146s in the sockets.
73,
Bill KU8H
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
|