Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

HP 400EL ac voltmeter
#1

 I'm trying to troubleshoot this tester due to erratic readings. I found the (Q7) voltage reading not right.
This transistor has a heat sink that pushes down on top of it. So it runs at least fairly warm. It is in a TO-18 package.
  It is staying cold to touch, any how the voltages called for on schematic are on the left. Mine on right.

Emitter   _-6.7v                                      Emitter -6.7v

Base    -7.4v                  My readings are: Base -7.4 v

Collector    -21.5v                                   Collector  -12v

above  readings were taken to ground with fluke DVM

 The collector voltage seems way low.

 The transistor has the # 3-009 on it. I'm trying to figure out what transistor equivalent to purchase.
It shows it being a PNP on the schematic, but the Mouser site has a 2n3009 as NPN.
http://www.mouser.com/ds/2/68/lssgp056-12668.pdf

 I'm confused Icon_crazy  Here is what mouser shows available.

http://www.mouser.com/Semiconductors/Dis...kaZ1z0y4cn

 Can someone advise me on which transistor I could use as a replacement? Thanks
 Here is the manual with schematic on page 45 and voltage chart on page 32.  all transistors on the tested within +/- 5% except the collector of Q7

file:///C:/Users/Mike/Downloads/400e_service%20(2).pdf
Sorry I see the download of schematic did not work will try to get it up


 
 








 
#2

Whooppppssss. Was looking at the wrong diagram! Your xsistor is HP p/n 1853-009. Couldn't find a crossover but are available here:     http://www.sphere.bc.ca/test/hp-parts/hpparts4.html  
For $7.
http://www.gellerlabs.com/HP%20400E%20EL.pdf

GL

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

Thanks Terry. I won't be on here for awhile. While looking for a schematic to download I clicked on a download that turned out to be some kind of virus/trojin hourse it took over the computer and know I'm trying to get rid of it.

By the way its called safefinder and I never seen one you could not uninstall till this one.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco model 38 code 121 not receiving signal.
Good luck next thing you know you will be winding coils just for the fun of it. DavidDavid — 11:29 AM
Testing a speaker and output transformer Trutone A2-G
morzh Short-circuited turns can be considered as a half-dead transformer. But on this case transformer will hot and s...Vlad95 — 11:01 AM
Testing a speaker and output transformer Trutone A2-G
I am not sure how a transformer could be weak. It could be inadequate, but only when you replace the original with somet...morzh — 09:56 AM
Philco model 38 code 121 not receiving signal.
Good news everyone! I think I have found everything I need for rewinding the antenna coil primary. I found some pla...Stormlord5500 — 09:40 AM
Philco Battery-WWII vintage
My younger sister went to SUNY Plattsburg NY, (BS, MS, RN) in the late 1970sabout 10 min from the Northern NY / Canada b...MrFixr55 — 07:59 AM
Philco Battery-WWII vintage
Hello Bob, What Amazing find! Sincerely Richardradiorich — 10:19 PM
Testing a speaker and output transformer Trutone A2-G
Hi Murf, Do this: Monitor between ground and one plate of the rectifier while playing the radio.  Do the same with ...MrFixr55 — 09:51 PM
Philco Battery-WWII vintage
Mike; I take it that Soviet cars did not come equipped with block heaters, hence the hot oil change? Where I lived in...Arran — 08:42 PM
Philco 42-345 Restoration/Repair
The more the better. (Within reasonable limits.) 2-5 times more is no problem in this case.Vlad95 — 03:50 PM
Philco 42-345 Restoration/Repair
Thanks, RodB and Vlad95, I was mainly trying to figure out this capacitor to locate a replacement, Vlad thank you for...osanders0311 — 03:44 PM

[-]
Who's Online
There are currently 1747 online users. [Complete List]
» 1 Member(s) | 1746 Guest(s)
Avatar

>