Topics

Tek 453A-1

Tom Gardner
 

On 01/11/19 12:05, Dale H. Cook wrote:
On 11/1/2019 6:52 AM, quadzillatech wrote:

well looks like ive wasted my time posting here so far !!
What are you in such a hurry for? I am sure that many who sub this reflector do not check it frequently. I hadn't checked it since your first post largely because, during most of that time, I was asleep.


On 10/31/2019 8:41 PM, quadzillatech wrote:

ive checked all the electrolytics for high esr,they all test good,
Did you do all of the power supply checks for the power supply adjustment? Which precision meter are you using for checking the low voltages? Which meter are you using for checking the HV test point? Do you have experience in troubleshooting and repairing instrumentation?

Do you have a second, working 'scope? The old adage is that you need a 'scope to fix a 'scope.
There is an "m3vuv" who is rebuilding a broken 30kV probe for use with a
Fluke 85 (and maybe an Avo 8),  choosing the resistors empirically.

https://www.eevblog.com/forum/projects/hv-probe/msg2761308/#msg2761308
Don't bother to read it all!

Dale H. Cook
 

On 11/1/2019 6:52 AM, quadzillatech wrote:

well looks like ive wasted my time posting here so far !!
What are you in such a hurry for? I am sure that many who sub this reflector do not check it frequently. I hadn't checked it since your first post largely because, during most of that time, I was asleep.


On 10/31/2019 8:41 PM, quadzillatech wrote:

ive checked all the electrolytics for high esr,they all test good,
Did you do all of the power supply checks for the power supply adjustment? Which precision meter are you using for checking the low voltages? Which meter are you using for checking the HV test point? Do you have experience in troubleshooting and repairing instrumentation?

Do you have a second, working 'scope? The old adage is that you need a 'scope to fix a 'scope.
--
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
https://plymouthcolony.net/starcity/radios/

Glenn Little
 

Be patient!! it has only been 10 hours since you asked for help.

Glenn

On 11/1/2019 6:52 AM, quadzillatech@... wrote:
well looks like ive wasted my time posting here so far !!


--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

quadzillatech@...
 

well looks like ive wasted my time posting here so far !!

quadzillatech@...
 

Hi all,ive the above scope,i brought it as faulty with no trace,after some poking around i found a couple of transistors dead on the z axis board along with a few resistors out of spec due to age,i now have a trace but cant adjust the high voltage to - 1950v,the most i get is -1093,the hv adjustment pot R900 makes no difference to the voltage whatsoever ive renewed the door knob on the eht comp but no change,the cal is all to pot due to the low hv,any ideas where to look and what to check?,ive checked all the electrolytics for high esr,they all test good,cheers m3vuv 73.