Date   

Re: 465 Missing a Few Components

Stephen
 

Thank you SCM. I already replaced the ones missing in mine with TIP35C, and reversed the B E leads.
But I’m sure this info will be very valuable to someone with a similar issue.
And I still haven’t found what is causing the new short on the 15V rail. But that’s ok.


Re: 465 Missing a Few Components

SCMenasian
 

I am in the process of replacing an MJE2901 and have found that, in addition to the 'K' part number which you mention, there is a "T" part number. The MJE2901T is a T0-220 part, while the straight MJE2901 is a T0-127 part
(the one we want). Also, The MJE2955 should be electrically compatible, as long as the module load is over a couple of mA. MJE2955s are more readily available on epay.


Re: 492P signal amplitude error and error 58

W1RS
 

I don't have a 492P, but while searching for a datasheet for some parts I have I saw that somebody was looking for an NEC mm765 RF amp that is used in this instrument. It is also known as upc1764A. If you find out that this might be the problem, I can supply you with NOS parts.

Good luck ,
Bob


Re: 2246 Flex PCB Interconnect - How Do You Disconnect Them Without Damaging Them?

Roger Evans
 

I hope someone will correct me if this is incorrect, I repaired a 2245A a couple of years ago which I then sold on. If these are the white ribbon cables with no obvious moulded on end connectors then they are just a push fit and need a little release agent such as IPA before pulling them out either with fingers or long nose pliers, trying to grip as much of the width of the cable as possible.

Beware the snap fit plastic connectors holding some of the boards together, particularly the front panel processor board. You need to _exactly_ reverse the disassembly sequence or the plastic locking button will break off!

Regards,

Roger


Re: Tektronix 465 Scope

Michael W. Lynch
 

On Sun, Apr 18, 2021 at 05:23 PM, Raymond Domp Frank wrote:




No “B”.
That makes it a Guernsey-produced instrument and a rather late one at that.
Non-US (i.e. non-B) numbers cannot be cross-referenced to applicable serial
numbers in the SM’s, which are all US (Beaverton-) related.
One of the most frustrating things when working on a Non-Beaverton Instrument. I ran into this myself when working on my Guernsey built 465 and a pair of Heerenveen built 468's.

--
Michael Lynch
Dardanelle, AR


Re: Tektronix 465 Scope

Bill
 

Thank you!! Yes it was a typo.
Bill


Re: Tektronix 465 Scope

Tom Lee
 

In cases where it is difficult to trace a signal from its point of origin forward, it may be easier to trace backward from some point downstream. Most likely you are looking for a shorted tantalum, and those stand out. A few quick ohmmeter measurements, and you’ll identify which are connected across the problem supply.

Just a thought, should obtaining a proper manual prove difficult.

— Tom

Sent from my iThing, so please forgive typos and brevity.

On Apr 18, 2021, at 4:49 PM, Bill via groups.io <ko4nrbs=yahoo.com@groups.io> wrote:

Page 174 in the 465 Service manual is the schematic of the scope's power supply.

On page 168 just underneath R1460 (Potentiometer) you can see R1463, CR1465, VR1414 and R1441. On my scope there are only two resistors in that spot and no diode.

Will just have to go hand over hand until I find the bad component on the -8vdc rail. My old 453 has an excellent manual but the manual is for it's serial number.

Bill





Re: Tektronix 465 Scope

Dave Peterson
 

Bill,

I presume you are looking at the early service manual, as "Fig 7-17 P/O A9 Interface circuit board" matches your description.

I think you have a typo: you meant VR1441?

Your description more closely matches the "SN B250000 & UP" service manual, "CRT Circuit" and "Fig 8-14 A9 - Interface circuit board".

I think Raymond is right, you have a Gurnsey (?) built scope, and the serial number does not fit the Beaverton "B" serial numbers distinguishing "early" and "later" constructions. I think you're describing the layout as depicted in the later service manual:

https://w140.com/tekwiki/images/5/55/070-1861-00.pdf

I'm still relatively new myself. I sometimes speak as if I know what I'm talking about. But this is what I think is going on.

Dave


Re: 492P signal amplitude error and error 58

Attilio
 

Is the YIG oscillator the 1st LO ?
Unfortunately I don't have a power meter to measure the power-level out of the YIG oscillator.
I could take a spare 1st LO and try to replace it.

--Cheers
Attilio


Re: Tektronix 465 Scope

Bill
 

Page 174 in the 465 Service manual is the schematic of the scope's power supply.

On page 168 just underneath R1460 (Potentiometer) you can see R1463, CR1465, VR1414 and R1441. On my scope there are only two resistors in that spot and no diode.

Will just have to go hand over hand until I find the bad component on the -8vdc rail. My old 453 has an excellent manual but the manual is for it's serial number.

Bill


Re: Tektronix 465 Scope

Bill
 

No it is a 465.
Bill


Re: Tektronix 465 Scope

Tom Lee
 

Ah, thanks, Raymond.

Sent from my iThing, so please forgive brevity and typos

On Apr 18, 2021, at 15:23, Raymond Domp Frank <hewpatek@gmail.com> wrote:

On Mon, Apr 19, 2021 at 12:07 AM, Bill wrote:


No “B”.
That makes it a Guernsey-produced instrument and a rather late one at that. Non-US (i.e. non-B) numbers cannot be cross-referenced to applicable serial numbers in the SM’s, which are all US (Beaverton-) related.

It’s not a 465B by any chance? The faceplate should show it.

Raymond





Re: Tektronix 465 Scope

 

On Mon, Apr 19, 2021 at 12:07 AM, Bill wrote:


No “B”.
That makes it a Guernsey-produced instrument and a rather late one at that. Non-US (i.e. non-B) numbers cannot be cross-referenced to applicable serial numbers in the SM’s, which are all US (Beaverton-) related.

It’s not a 465B by any chance? The faceplate should show it.

Raymond


Re: Tektronix 465 Scope

Tom Lee
 

Are you sure about that?

Sent from my iThing, so please forgive brevity and typos

On Apr 18, 2021, at 15:07, Bill via groups.io <ko4nrbs=yahoo.com@groups.io> wrote:

No “B”.
Bill





Re: Tektronix 465 Scope

Bill
 

No “B”.
Bill


Re: Tektronix 465 Scope

 

On Sun, Apr 18, 2021 at 07:39 PM, Bill wrote:


Anyone have a service manual that covers a 465 scope serial number 107659
Is that B107659?

Raymond


7L14 for sale

Michael Perkins
 

I have a 7L14 in excellent shape for sale. If interested, I can send pictures of the unit operating. I have not used it much in the last 8 years, but it works well. I will consider offers , but reserve the right to ignore low - ball offers. I'm looking for $950.00 for the instrument.Mike


some classic HP 38/48 calculators added to stuff season

 

More clean up from my office, some mint 38G, 48S and 48SX hp
calculators added to the stuff season page, have a look here:
https://www.sphere.bc.ca/test/stuffday.html#hpfans

I am happy with just my model 20S at this point.

all the best,
walter (walter2 -at- sphere.bc.ca)
sphere research corp.


Re: 492P signal amplitude error and error 58

ulf_r_k
 

I am sorry to hear that replacing U1050 and U2050 did not help.

What is the power-level out of the YIG oscillator?

BR

Ulf Kylenfall


Re: Tektronix 465 Scope

Bill
 

I will do that later today. Found it frustrating to try and trace the circuits when components are not where they are supposed to be.
Bill

3141 - 3160 of 184569