Knobs and buttons for old Tek 2465 scopes

Joerg wrote in news:OI8zh.8661$ snipped-for-privacy@newssvr11.news.prodigy.net:

Take off a few good knobs,use modeling mold materials to cast new ones.

Not that I'm aware of.

Not really.

"nicotine brown";you SMOKE around your gear? That's not going to help it any.Nor will direct sunlight/UV. (BTW,plastic outgasses plasticizers naturally,becomes more brittle.)

I don't agree with this.

IIRC,the lever switches used for triggering modes is part of the switch itself,not separate.

My guess is that you need a parts scope to cannabalize.

Several people on news:rec.antiques.radio+phono routinely make replacement knobs. Look for Jeff Angus. He is in California. There are a number of others doing this work, as well:

That's hard with the time base / trigger mode knob. Very thin and no clearance to speak of behind the panel.

Nah, no smoking here. This was at a client, also non-smoking of course. It's just age. Wish they had used metal for that switch ring.

Well, I had my (not so good) experiences with plastic parts that were NOS.

They are separate. A SPDT switch "standing up" and the gray plastic part cradles the rocker with some clearance.

Yes, the client will do that but it would need to be a younger scope.

Or we'll drill a hole and hang a plunger onto the switch. It will look ugly but work ;-)

Thanks, Michael! That's the kind of info I was looking for. Might not work for the trigger mode ring because it's a flimsy design to begin with but it may work for all the other little knobs that crumbled. The trigger mode might become a "kludge stick" out a hole drilled into the front panel ;-)

Try this:

;-)

-- Rgds, Stefano

The main problem is molders who run the parts too fast into molds that are too cold. They're OK for a while but will crack over time.

Thanks, Stefano! Great, they seem to have quite a few of the knobs that broke. Couldn't find any street address on the site, that always has me a bit concerned but if they have the right stuff it may be ok. Did you use this company before?

Just told my client about qservice. They had already found that company on the web and the knobs are on order. To my surprise they even had that weird delayed-trigger clutch which started all this grief. Since that seems to be something that easily breaks here is the photo in case anyone else runs into the same problem:

Thanks again.

The last I heard, jeff was machining new brass inserts for his replica knobs. Jeff is a bit rough around the edges, but I think he can do what you need. If he can duplicate them, I'm sure he'll make extras to keep on hand.

Well, just talked to my client and they have already ordered from the source Stefano mentioned. But thanks anyway, I am going to write this into my database for parts sources in case a knob or button turns out to be truly unobtanium.

If you are going to cast, why not use metal? OTH, if that ring must be clear, use a sheet of polycarbonate of similr thickness (rather rigid and robust) as a "base" for the cast section.

Hi Joerg, I'm glad to read that you find useful this information, I've just acquired some items on eBay from qservice and I'm waiting to receive these in the next days.

Polycarbonate would be an option. Metal wouldn't be because a lot of the scope's knobs have spring action parts molded into them. I wish Tektronix hadn't done that.

Anyhow, the client has already ordered from a spare knob manufacturer. So there does seem to be a sizeable market for that old 2465 scope. IMHO it was one of the best Tektronix ever made which is why I convinced that client to buy some. This client has several newer digital TDS scopes but they don't even come close to the old 2465 when chasing noise on pulsed signals. What does work nicely is the 7000 series mainframes which I am using here. Much better "knob quality", none of this plastic snap action stuff that breaks off, all nicely done with metal core and set screw. But they are too large and too heavy for field work.

My client had found this source the night before and ordered right away. But you'll probably win the race to receive the parts because they said the company is in Greece and you are only a few hundred miles from there. It's over 6000 miles for us here.