¿ªÔÆÌåÓý

Re: R15 and ADE-1 mixer getting very hot


 

raj jee,
?There is no heat without ade-1 in place even if the pins 1and 6 are connected with a wire to maintain continuity.
?
Thus it is clear that the trafo inside the mixer covering pins 1&6 is f\getting breakdown (short under real voltage application) to the secondary? and that has middle ground.

Perhaps it would be easy to check placing ade-1 on board and isolating pins 4&6? from ground. later one could connect one by one? pins 4 and 6.
It would show up?

?I finally suppose a case of insulation break down, in real working condition.
regards
?sarma
?vu3zmv

On Fri, Apr 28, 2017 at 6:57 PM, William Hemmingsen <lee.hemmingsen@...> wrote:
Raj,


1-6 - 0 ohms
2-5 - .216v in both direction
3-4 - 0 ohms


W4WHL

On Fri, Apr 28, 2017 at 8:37 AM, Raj vu2zap <rajendrakumargg@...> wrote:
William,

Please check the continuity of your ADE-1ASK again.

1-6 - 0
2-5 - Diode check both polarity should be same reading
3-4 - 0

My guess is continuity between these pins but not between others.

I have a few but could not find it to confirm, maybe someone could confirm the above!

With the ADE not soldered, shine a bright light from the component side and check for shorts (most likely) between
4/5 and 6, trace all the way to Q7. Check if there is a short to ground at collector of Q7 or the track leading to it
from ADE pin 6.

Put the ADE back, without power and check for short to ground from ADE pin 1 and 6.
My guess is that only a short to ground between ADE pin 6 to Q7 can cause the ADE to heat up along with R15!

73
Raj, vu2zap



1-2 19k ohms
1-3,4,5 open
1-6 0 ohms (RF Primary)
2-3 42k ohm
2-4 open
2-5 19k ohms <<<<<<<<<<<<< diode
2-6 19k ohms
3-4 0 ohms (LO Primary)
3-5 open
3-6 open
4-5/6 open

?? Pin 2 & 3 both go to blocking capacitors c18,c19,c11,c15 on RF & IF Amps.?? I tested these pins to ground on the board and they are open as expected.?? This means the short must be in the ADE-1 itself, and only when power is applied.
Looking at the bottom of the ADE-1, there are 2 wires on pin 1.?? I expect these are RF primary and secondary ground.
This is very strange

W4WHL





--
Regards
Sarma
?

Join [email protected] to automatically receive all group messages.