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On 2/3/24 15:16, cheater cheater wrote:

Someone smart just told me to use castellations on the edge of a board
to solder the flat cable to. What are your thoughts everyone? I guess
I would just span the ribbon across the castellated edge, and then
burn the hell out of it with a hot bar until it's soldered.

Will you sketch that? Not getting a mind picture yet...

Hi Luca,
I think 2465B and 2467B share the same supply schematics. Based on my experience with 2467B:
- Component diagram may have C1132 and C1115 swapped (wrong). While desoldering take a note of the original value to make sure.
- NTC resistors RT1010 and RT1018 drifted quite a bit on my unit and most importantly R1010 was open circuit with a burn mark, check R1019 too. I replaced them with flameproof resistors.

Ozan

Self made

On Sat, Feb 3, 2024 at 11:25?PM Greg Muir via groups.io
<big_sky_explorer@...> wrote:

For use on what make/models of equipment? Different extenders used on different equipment.

Greg

Some 153- parts have matching criteria published in Tek's Common Design Parts Catalog. Look in the Diodes and Transistors volume archived at w140.com .

Dave Wise
________________________________
From: [email protected] <[email protected]> on behalf of n4buq <n4buq@...>
Sent: Saturday, February 3, 2024 12:23 PM
To: tekscopes <[email protected]>
Subject: Re: [TekScopes] High-Amplitude High-Frequency Oscillations in 7704A LV Regulator

Yes - I noticed they were selected as well but, like you say, we don't know the criteria. New 2N3053s have a range of 50 to 250 for hFE so I suppose it's a crap-shoot as to what one gets.

Thanks,
Barry - N4BUQ

On 2/3/2024 1:11 PM, n4buq wrote:

I have three transistors with which I can use to test for Q32143:

I am late joining this thread, and although I have look at the previous
posts in this thread my remarks may already have come up.

Note that Q32143 and Q3220 are shown on 7704A change sheet M32489, dated
17May1978, as selected parts. The selection criteria are not shown on
the change sheet, but, in my experience, the most common selection
criterion for Tek and HP selected transistors is hFE.
--
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA

For use on what make/models of equipment? Different extenders used on different equipment.

Greg

Someone smart just told me to use castellations on the edge of a board
to solder the flat cable to. What are your thoughts everyone? I guess
I would just span the ribbon across the castellated edge, and then
burn the hell out of it with a hot bar until it's soldered. Think the
melting / burning insulation would pose a problem with the solder
joints? Bear in mind this is just for audio.

This is a transit connector:

@John: Bin d'Aire-Dunndad, works reasonably well.
Just not for 100+ pieces (= 200+ cable ends)...
FPC has the disadvantage of being less flexible.

For the housing: 3D printing can be succesful if the material is chosen wisely. For 200+ housings one might even be looking at injection molding,the molds can be relatively cheap if they do not need to last long. Clever design would mean a housing built with two identical parts.

emissionlabs:

I have bad experience of silicon grease in combination with switches.
The silicon floats around after some years and may end up in the contacts.
This is easily seen with the silicon thermal paste that sooner or later covers a big part of the cooling flange.
I saw in the HP service manual for 8340A, vol 3, page 56, that HP specify oil based thermal compound and warn about using silicon based thermal compound due to reliability issues as the TO-3 transistors are mounted in small pin-sockets.
The oil based will dry with time though.

The microwave oven I still have, has this silicon grease in the mechanics. After some years it became more and more difficult to set the cooking time. I who likes to see "whats inside", took the rotating digital switch apart and found this. After cleaning thoroughly it worked fine for many years until fairly recently the same thing happened again. I took it apart again and now it works just fine again. I'm not 100% sure it really is silicon in the switch, but it looks like it is.
At my work we were also warned not to use it.

These Tektronix push switches I have seen before in some other old equipment, and even took one switch apart for some forgotten reason. Cannot even remember where and when, quite some time ago. I think they are "standard" and you specify what combination and functionality you want.
From what I understand, there were at least two US manufacturers, compatible but slightly different (color?).

Bo

Hi all

Thanks for all your inputs. I found some Excel sheets about the capacitors and will go through the boards first. Maybe I'll also do the big main board.. I don't trust any late 80s until early 00s capacitors anymore I've seen too many failed ones.

When I'm done with this or hit a snag I'll come back to this thread. Regarding the Dallas, good idea recording the calibration data. I got a video with the data for the 2465B. I hope I can do the same with the other scope after I get it running again and nothing is lost yet.

The DS1230Y/AB still has batteries, that would have been to easy...

I found this document with several solutions for replacing the Dallas chips
(after going through that PDF I'll try to find the reasoning against and then make a decision)

On 2/3/24 13:51, cheater cheater wrote:

Thanks John, have you ever soldered large conductor count ribbons like
that? What about ones at 0.64mm pitch? How did that go, did it need a
lot of rework, etc?

0.5mm pitch lqfp packages I've done, and there is no rework -- you just see the state of it and when all is good, you stop.
Use magnifiers -- that can be a luxo lamp with big lens, head mounted lenses, swing arm mounted microscope with zoom, etc.

Don't hold with hand, use a "third hand" thing to put some force down on it, or some kind of clamp arrangement with clothes pins, rubber bands, etc.

I wonder, during manufacture, is it possible to strip a flat cable's
isolation by melting / burning it away with a hot bar?

On Sat, Feb 3, 2024 at 9:51?PM cheater cheater
<cheater00social@...> wrote:

Thanks John, have you ever soldered large conductor count ribbons like
that? What about ones at 0.64mm pitch? How did that go, did it need a
lot of rework, etc?

On Sat, Feb 3, 2024 at 9:48?PM John Griessen via groups.io
<john@...> wrote:

On 2/3/24 13:41, cheater cheater wrote:

I wonder how difficult it would be to do everything with a 0.64mm
pitch flat cable, probably very...

Just hold it down, flux it up, and it will solder well.

Thanks John, have you ever soldered large conductor count ribbons like
that? What about ones at 0.64mm pitch? How did that go, did it need a
lot of rework, etc?

On Sat, Feb 3, 2024 at 9:48?PM John Griessen via groups.io
<john@...> wrote:

On 2/3/24 13:41, cheater cheater wrote:

I wonder how difficult it would be to do everything with a 0.64mm
pitch flat cable, probably very...

Just hold it down, flux it up, and it will solder well.

On 2/3/24 13:41, cheater cheater wrote:

I wonder how difficult it would be to do everything with a 0.64mm
pitch flat cable, probably very...

Just hold it down, flux it up, and it will solder well.

The connector is already decided, it is the PCIE x1 connector. All I
need to figure out is how to solder a ribbon to a pcb with minimal
effort and cost and rejects, and how to house the whole thing (pcb +
ribbon) in a cartridge-style enclosure.

On Sat, Feb 3, 2024 at 8:04?PM Jared Cabot via groups.io
<jaredcabot@...> wrote:

I would be looking at IDC connectors, like what was used on old PATA hard disk drives, or FFC/FPC cables and connectors.

The former is bulkier but can carry more current and endure more flexing.
The second is more delicate but is much lower profile.

The FFC cable could feasibly be soldered directly to the PCB if you want to forgo using connectors.

Also, thr male side of the IDC connection could be edge mounted at a stretch to make things lower profile than a 90deg connector, depending what your fab house is willing to fiddle with.


Jared

Thanks Leo, what are transit connectors?

I was thinking of soldering the ribbon cable on a diagonal. So if the
pcb is 25mm wide, and x mm long, then the diagonal is sqrt(25^2 + x^2)
mm long. Since the diagonal would have to be 1.27mm * 32 = 40.62 mm, x
solves to 32mm. Which is perfectly within reason.

I wonder how difficult it would be to do everything with a 0.64mm
pitch flat cable, probably very...

On 3 Feb 2024, at 19:01, DaveH52 <ac2gl.dave@...> wrote:

Have a look at the DS1230Y/AB nonvolatile RAm it uses EEPROM or FLASH memory and NO BATTERIES REQUIRED!

The data sheet at mentions “lithium energy source” which is presumably the usual battery.

Yes - I noticed they were selected as well but, like you say, we don't know the criteria. New 2N3053s have a range of 50 to 250 for hFE so I suppose it's a crap-shoot as to what one gets.

Thanks,
Barry - N4BUQ

On Wed, Jan 31, 2024 at 10:19 AM, Tom Lee wrote:

Indeed! A partial list on vintagetek:

I forgot I had a news blog about the reorganized movies. I haven't been keeping it up. The list I keep up is on the main movies page at

I try to put all the leads we get, but candidly don't have the time to find the movie and watch it to find the scene. If people would do a screen capture and send that to the museum along with the movie title and approximate time I'd be more than happy to add them to the website.

Dave

On 2/3/2024 1:11 PM, n4buq wrote:

I have three transistors with which I can use to test for Q32143:

I am late joining this thread, and although I have look at the previous posts in this thread my remarks may already have come up.

Note that Q32143 and Q3220 are shown on 7704A change sheet M32489, dated 17May1978, as selected parts. The selection criteria are not shown on the change sheet, but, in my experience, the most common selection criterion for Tek and HP selected transistors is hFE.
--
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA

I would be looking at IDC connectors, like what was used on old PATA hard disk drives, or FFC/FPC cables and connectors.

The former is bulkier but can carry more current and endure more flexing.
The second is more delicate but is much lower profile.

The FFC cable could feasibly be soldered directly to the PCB if you want to forgo using connectors.

Also, thr male side of the IDC connection could be edge mounted at a stretch to make things lower profile than a 90deg connector, depending what your fab house is willing to fiddle with.


Jared