Date   

Re: Tek 453 - Q913 Part Number

zenith5106 <zenith@...>
 

--- In TekScopes@yahoogroups.com, "nu7f" <jbstamper@c...> wrote:
I have an early (Serial 009869) Tek 453 scope with no trace. Q913
on the Z Axis board appears to be the only transistor in this unit
that is not original. Can someone give me the correct tek part
number or sub for Q913? I'm hoping it is just the transistor
before
I go digging into the HV side.

Thanks,
John
----------
My microfiche RPR (replaceable parts record) says that 151-0133-00 is
replaced by 151-0220-00 at all occurrences in 453, all S/N's, except
for Q423, Q753, Q754, Q775 and Q785 where no replacement is listed.
You can find a scan of this page at
http://w1.871.telia.com/~u87138090/
/Zenith


Re: Tek 453 - Q913 Part Number

Miroslav Pokorni
 

Do not blame Walter, that might be his or Tek's mistake. God knows manuals
have more than a fare share of typos and various other mistakes.

As for detective work, there is something to be desired in drawing
conclusion: 'if both transistors cross reference to the same NTE number,
then those transistors must be same' . Let us keep in mind what is purpose
of NTE numbers: to supply TV repair shops and as a side line a supplier for
home brew projects.

It is true that National Semiconductor makes both transistors on the same
process (#66) and gain seems to be similar for several currents shown in
listing. However, the package is different and transit frequency and turn
off times are quite different:

Package fT toff

2N3251 TO-18 300 250

2N4122 TO-92 450 150



Regards

Miroslav Pokorni

----- Original Message -----
From: "Rolynn PRECHTL K7DFW" <k7dfw@clatskanie.com>
To: <TekScopes@yahoogroups.com>
Sent: Friday, November 14, 2003 9:58 PM
Subject: Re: [TekScopes] Re: Tek 453 - Q913 Part Number




Checking the NTE cross reference, both the 2N3251 and the 2N4122 are
PNP, and are crossed to NTE 159.
============================
Darn, it appears I was hornswaggled by the internet again.

Got the info from here......
<http://www.reprise.com/host/tektronix/reference/transistor.asp>
where it's claimed to be a NPN......

"Transistor type 2N4122 has been assigned the following Tektronix part
numbers:
Tek Part Number Remarks
151-0493-00 NPN, SI"

I should know better and consult my Tek semiconductor catalog instead of
trusting the www.

K7DFW

..._._




Re: Tek 453 - Q913 Part Number

ROLYNN PRECHTL K7DFW
 

Checking the NTE cross reference, both the 2N3251 and the 2N4122 are
PNP, and are crossed to NTE 159.
============================
Darn, it appears I was hornswaggled by the internet again.

Got the info from here......
<http://www.reprise.com/host/tektronix/reference/transistor.asp>
where it's claimed to be a NPN......

"Transistor type 2N4122 has been assigned the following Tektronix part
numbers:
Tek Part Number Remarks
151-0493-00 NPN, SI"

I should know better and consult my Tek semiconductor catalog instead of
trusting the www.

K7DFW

..._._


Re: Tek 453 - Q913 Part Number

Howard Matthews
 

Checking the NTE cross reference, both the 2N3251 and the 2N4122 are
PNP, and are crossed to NTE 159.

Combine that with the fact that although the parts list for Q913
listed the two different transistors for different serial number
ranges, the schematic showed no substantial changes at the same SN
break point, I've come to this tentative conclusion:

Tek got tired of selecting 2N3251s, and found that 2N4122s did the
job better. So, I believe the 2N4122 would be the prefered
replacement for any Tek 453 Q913, SN 100 to 19,999 (and also SN >
20K) - unless you have an early model that you *absolutely must*
restore to *factory mint* condition.

I'm new at this repair game, so if my detective work is wrong, I
would like to be corrected. :]

-Howard

--- In TekScopes@yahoogroups.com, "Rolynn PRECHTL K7DFW"
<k7dfw@c...> wrote:



Q913 - Tek pn 151-0220-00 Silicon 2N4122 for Type 453
oscilloscope
===========================

Now I'm confused.

My manual, with SN 4395 written in, shows 913 as a 0133-00 which
is a
selected 2N3251 (a PNP) and the schematic shows it as a PNP.

That 2N4122 is a NPN.

K7DFW

..._._


TEK 211 Scope & Manual FS/FT

w1ksz <w1ksz@...>
 

I picked up a Tek 211 on e-bay. It doesn't turn on and I
don't have the time nor patience to troubleshoot it.
It comes with the original scope probe and an original
Tektronix Service Manual.
I would swap it for something I could use (7A29, 7B10, 7B15, etc)
Anyone want it ?

73, Dick, W1KSZ


475 Vertical Position control problem

ehsjr@...
 

My 475 just developed this problem:
On either ch1 or ch2, I cannot properly control the vertical position of the trace,
in any mode - single channel, alt, chop, add.

The control does move the trace, but not smoothly, and never below about the
middle of the screen. The kicker is that either vertical position control moves
the trace for "it's own" channel and for the other channel.

Any pointers before I start? Fortunately, I just finished repairing the
Z axis amp on my other 475, so I'm not scope-less. Thanks in
advance for any help you can offer!


Re: Tek 453 - Q913 Part Number

Howard Matthews
 

Repeating my private post (I guess, I'm still learning how the posts
work on Yahoo)...

The serial number given indicates the proper part number for Q913 is
the "selected" 2N3251, PN 151-0133-00. At SN 12680 this circuit was
redesigned and Q913 became PN 151-0220-00, a 2N4122 with no
indication that it was specially selected. My parts list is very
clear about this, my schematic is less clear, but shows a PNP.

If you have the right part in your scope, you can get a general idea
whether Q913 and it's surrounding parts work by measuring: Base=-
0.24V, Emitter=-0.18V, Collector = -3.8V. (Hmm, I'm guessing that's
a Germanium because of the .06V base-emitter voltage. That seems
low even for Germanium, but that is what the schematic says.)

But before you blame the Z-axis for lack of trace, check the
horizontal and vertical deflection pins on the CRT. They should all
be, or Horz/Vert centering should adjust to, about 47-48V. A
failure in either the horizontal or vertical amp boards can drive
the trace off the face, and appear as though there is no trace. I
know, I just fixed a "no trace" 453 with a bad transistor in the
vertical amp. It's a real smiley face experience to replace a
transistor in a $19 "parts scope" and suddenly get a decent trace!

Good luck,
-Howard

--- In TekScopes@yahoogroups.com, "Rolynn PRECHTL K7DFW"
<k7dfw@c...> wrote:



Q913 - Tek pn 151-0220-00 Silicon 2N4122 for Type 453
oscilloscope
===========================

Now I'm confused.

My manual, with SN 4395 written in, shows 913 as a 0133-00 which
is a
selected 2N3251 (a PNP) and the schematic shows it as a PNP.

That 2N4122 is a NPN.

K7DFW

..._._


Re: Tek 453 - Q913 Part Number

ROLYNN PRECHTL K7DFW
 

Q913 - Tek pn 151-0220-00 Silicon 2N4122 for Type 453 oscilloscope
===========================

Now I'm confused.

My manual, with SN 4395 written in, shows 913 as a 0133-00 which is a
selected 2N3251 (a PNP) and the schematic shows it as a PNP.

That 2N4122 is a NPN.

K7DFW

..._._


Re: Tek 453 - Q913 Part Number

Rex W. Athey <mister_twister@...>
 

Q913 - Tek pn 151-0220-00 Silicon 2N4122 for Type 453 oscilloscope

part of HV regulator circuit - Q914, Q913, Q923 - Q 930 is the HV osc transistor that drives the HV transformer. F937 2 Amp fuse for the circuit.

Hope this helps.

Rex W. Athey


Tek 453 - Q913 Part Number

nu7f <jbstamper@...>
 

I have an early (Serial 009869) Tek 453 scope with no trace. Q913
on the Z Axis board appears to be the only transistor in this unit
that is not original. Can someone give me the correct tek part
number or sub for Q913? I'm hoping it is just the transistor before
I go digging into the HV side.

Thanks,
John


Re: Digest Number 917

Sam Reaves
 

Brad,

You might be able to find someone who will trade you a regular unit for the
spectrum analyzer graticule version. That's probably easier than trying to
find the board you are looking for.

Sam
W3OHM


TekScopes@yahoogroups.com wrote:


There is 1 message in this issue.

Topics in this digest:

1. Re: 7613 HV problem
From: "Brad Hernlem" <alibhernlem@yahoo.com>

________________________________________________________________________
________________________________________________________________________

Message: 1
Date: Mon, 10 Nov 2003 22:17:03 -0000
From: "Brad Hernlem" <alibhernlem@yahoo.com>
Subject: Re: 7613 HV problem

Phil,

I have one of those scopes. When I acquired it the HV section was
non-functional and in partial disassembly. After first thinking that
the big oscillator transistor was bad and after replacing the HV
rectifier, I discovered that the real problem (probably) was that the
HV cap was leaky and had to be replaced. The scope has been running
for several years (although I don't work it too hard). I'll have a
look at my manual and see how your parts difficulties compare to what
I observed.

Also, my 7613 has no readout board (I would LIKE one if anyone has
one, BTW ... hint, hint) and so, YES, the scope can run just fine
without it. My scope is USAF surplus and I think was originally
configured as a spectrum analyzer (hence, no readout board, has log
scaled graticule, &c.).

Brad KG6IOE

--- In TekScopes@yahoogroups.com, "Stan & Patricia Griffiths"
<w7ni@e...> wrote:
I don't recall seeing a response to this one. I checked the
Modification
Summary to see if failures of these parts are common and fixed by some
change in the 7613. Sorry, no luck there . . . I don't really have any
other suggestions for you but I thought you would want to know that I
researched for you anyway . . .

Sorry about the long delay. I'm swamped!

Stan
w7ni@e...

----- Original Message -----
From: "sittners" <sittners@s...>
To: "tekscopes" <tekscopes@yahoogroups.com>
Sent: Saturday, August 09, 2003 11:15 AM
Subject: [TekScopes] 7613 HV problem


I need a little help here and throw my open question out to the
group. I
have a 7613 that continues to blow the HV regulator transistor,
Q1314, and
diode CR1215 (from the collector of Q1314 to ground). The switching
transistors Q1216, Q1218 are fine, and the rectifiers test OK. How
can I
go
about isolating the problem; also, can the scope operate with the
readout
system board disconnected.

Phil
________________________________________________________________________
________________________________________________________________________

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/


Re: 7L13 Service Manual

ROLYNN PRECHTL K7DFW
 

The manual has been claimed.

Thanks,

K7DFW

..._._


Thank you!

rollsroyce1_92394
 

Many thanks to all of you who kindly responded to my earlier
post, "Which scope to buy?". My electronics experience is limited to
some soldering and basic use of a multimeter, with my last formal
electronics class having been in high school during the late 60's,
so your answers were very helpful. I now have a Tek 485 scope,
manual, and probe set on the way and am looking forward to learning
to use it.

Thanks again for your help and guidance!

Royce


7L13 Service Manual

ROLYNN PRECHTL K7DFW
 

Used but very good condition 7L13 service manual. Still in shrink wrap from
commercial seller.

Unwanted purchase. Really needed a 7L14 manual.

$47.00 + Priority Mail. Slightly less than I paid for it.

Rolynn

..._._


1A7 manual download?

Scott Newell <newell@...>
 

A friend is wanting to study the common mode circuitry in the 1A7 front
end...I thought I had the book, but nope, I've got a 1A6 and 7A22 instead.
Anyone seen a 1A7 scan on any of the free manual repositories?


newell N5TNL


Tek 1106 Battery Pack for Parts-Free For The Shipping

Jim Reese
 

Hello Tekkies,

I have an 1106 that is destined for the trash that is good for
parts. The paint is peeling off of the case cover (can be repainted)
and the batteries are bad/old. The round battery level meter is
broken. Everything else (PCBs and transformer) looks OK and in
decent shape (not corroded). It is free to the first one that wants
it for the shipping cost from Dayton, Ohio.

Jim Reese


TEK 211 Problem

w1ksz <w1ksz@...>
 

I picked up a TEK 211 on e-bay and of course it doesn't work. It
doesn't even turn on. I verified power is getting into the scope and
the fuze is OK, but before I dis-embowel it, does anyone have any
hints on what to look at ? Any common failure mechanism I should look
at ? I do have the Service Manual for it.

Thanks, Dick, W1KSZ


Re: 7613 HV problem

Brad Hernlem
 

Phil,

I have one of those scopes. When I acquired it the HV section was
non-functional and in partial disassembly. After first thinking that
the big oscillator transistor was bad and after replacing the HV
rectifier, I discovered that the real problem (probably) was that the
HV cap was leaky and had to be replaced. The scope has been running
for several years (although I don't work it too hard). I'll have a
look at my manual and see how your parts difficulties compare to what
I observed.

Also, my 7613 has no readout board (I would LIKE one if anyone has
one, BTW ... hint, hint) and so, YES, the scope can run just fine
without it. My scope is USAF surplus and I think was originally
configured as a spectrum analyzer (hence, no readout board, has log
scaled graticule, &c.).

Brad KG6IOE


--- In TekScopes@yahoogroups.com, "Stan & Patricia Griffiths"
<w7ni@e...> wrote:
I don't recall seeing a response to this one. I checked the
Modification
Summary to see if failures of these parts are common and fixed by some
change in the 7613. Sorry, no luck there . . . I don't really have any
other suggestions for you but I thought you would want to know that I
researched for you anyway . . .

Sorry about the long delay. I'm swamped!

Stan
w7ni@e...

----- Original Message -----
From: "sittners" <sittners@s...>
To: "tekscopes" <tekscopes@yahoogroups.com>
Sent: Saturday, August 09, 2003 11:15 AM
Subject: [TekScopes] 7613 HV problem


I need a little help here and throw my open question out to the
group. I
have a 7613 that continues to blow the HV regulator transistor,
Q1314, and
diode CR1215 (from the collector of Q1314 to ground). The switching
transistors Q1216, Q1218 are fine, and the rectifiers test OK. How
can I
go
about isolating the problem; also, can the scope operate with the
readout
system board disconnected.

Phil


3L5

Craig Sawyers <c.sawyers@...>
 

Hi all

Heads up to those who are looking for a 1L5. There is a 3L5 (same as 1L5
spec, but fits a different scope) in its host 564B storage scope on eBay at
the moment item 2570840028. The guy has it on at a starting price of $25.

Craig


Tek 2337 Calibration

rodneyks7 <rksommerville@...>
 

Hi,
I have recently aquired a 2337 in need of calibration, I have a
collegue that can do it for me. However the only problem is I require
a service manual or part there of. Can anybody help?

Thanks in advance

Rodney

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