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If you have an original foot, I can make a mold and pour plastic feet. I've already done it for some older Yaesu and Kenwood rigs.

Vince.

--
Michigan VHF Corp.

Hi Bert,


That would be great. Even though the foot has the same part number on the 314, it would be good to confirm correct fit on that unit. Let's wait until I get results from Lee - I actually sent him several variants to try to get the best fit. Once that's determined, I can send you a sample of that size.


PM me your address, please.


Jeff

________________________________
From: [email protected] <[email protected]> on behalf of Bert Haskins <bhaskins@...>
Sent: Thursday, March 15, 2018 9:39 AM
To: [email protected]
Subject: Re: [TekScopes] Back feet for 335 scope



On 3/15/2018 11:07 AM, Jeff Davis wrote:

Hello all,

Here's an update on the project to develop replacement back feet for the Tek 335 scope. Lee Houde has graciously provided me with a sample foot, which I've measured and modeled. I sent a first set of samples to Lee, which he fitted to his scope. They worked and were usable, but not perfect. Lee gave me some great feedback and some photos which I used to revise the models and print a second set. They're on their way to Lee now. With any luck they'll be a great fit and I'll send out another update to the group at that time.

Jeff

If you would like another tester, I would be happy to volunteer.
I have a 314 and a 335.

Thanks,
Bert

On 3/15/2018 11:07 AM, Jeff Davis wrote:

Hello all,

Here's an update on the project to develop replacement back feet for the Tek 335 scope. Lee Houde has graciously provided me with a sample foot, which I've measured and modeled. I sent a first set of samples to Lee, which he fitted to his scope. They worked and were usable, but not perfect. Lee gave me some great feedback and some photos which I used to revise the models and print a second set. They're on their way to Lee now. With any luck they'll be a great fit and I'll send out another update to the group at that time.

Jeff

If you would like another tester, I would be happy to volunteer.
I have a 314 and a 335.

Thanks,
Bert

For all those GHz digitizer junkies out there...

Bonjour Patrick,

Can you take a picture of the board showing the area of t he resistor? Give us a link to the picture as you cannot attach it to the message.



Regards

On 03/12/2018 05:58 PM, Benjamin A wrote:

My real question is: should I even be trying this right now? Should I stash this scope away, get a crappy digital toy to learn from and tackle this in the future? That would be a bummer, but I don't want to either make things worse or hurt myself (although I know enough to stay away from the mains/high voltage sections). Is there a way to find a local wiz to help learn how to troubleshoot it?

This is the place to ask. What is your local definition? You didn't say.

"I've read some of the service manual and some of the threads on here and people seem to imply that the low voltage power supply is the first thing to check, followed by the horizontal amp, but..."

That's the right order to do things in.

Thanks Harvey, Raymond, Craig, HenkC and Roger for your last contributions (To all others as well, I can't catch up with all the answers).
I must say that it's a joy to participate in this group. So much knowledge in so many areas!
I will summarize my comments... To avoid too deep threads.

On Raymond's and Craig's clarification to Harvey remark on the direct interface plug-in (and required modification of the MF)... Wow, connect directly to the CRT's plates...that's a radical approach! I imagine the equalization networks required to "tame" the interconnect cables characteristics, as well as to compensate for the plate's capacitance...

On HenkC's remark about the requirement (or lack thereof) for a standardizer... Acknowledged!
As this thread progressed, I was able to gather a few pros and cons about following the "strict" path to calibration of this unit, versus a more flexible one...
My conclusion was that, at least DC wise, which is relatively easy to achieve even without a standardizer or an extender, just a DMM, I will pursue getting the MF calibrated to standard (thanks Roger, for the suggestion to tap into the Plug-in Output's and for the reminder on the "isolated" DMM... Never fear... I don't have a bench DMM, only a handheld one).
As for AC and Step response wise.. I think I will just try to get the best system wide response of the set (7623A + 7A26) calibrating the whole thing as if it would be one.

On Roger's answer... Yes you were able to add. Indeed it was the first time I saw an reference on what is the actual expected deflection factor (50mA into 50R / div).
I sort of knew that it was around that ballpark, by looking at the 7B53A output waveforms, and wild guessing that the deflection factors adopted for both the horizontal and vertical compartments were the same (it had to be, if X-Y operation was to be accurate by any measure).

Rgrds,

Fabio

Since this is a bit of an FAQ, I'm replying to myself in order to change
the topic and make it more visible.

On 2018-03-15 11:25 AM, Fabio Trevisan wrote:

Guys,
Though it seems we're already discussing what to do AFTER the damage is done... Are there suggestions for ways to prevent it from happening when the labels are still intact and one wants to clean them?
Nail polish maybe? (will it dissolve the label's paint)?

Yeah, knowing of a harmless lacquer would be excellent info.

Drawing Protective Lacquer (spray can)? Don't know what's the correct name for this in English... Here we find it in Design and Drawing stores, to apply over pencil drawn sketches, so they won't wipe or get smudged on handling. Will the lacquer stick well to the plastic and don't "lift" the labels?

"Fixative". I doubt this will work. It will probably rub off quickly and
may also attract dirt. It's probably only good for paper.

--Toby

What about removing the yellowish tint? The solution used by retro-computing and retro-gaming folks, of using 40Vol Hydrogen Peroxide + TAED (the oxygen activator present in OxiClean) + Sun Light... Will it wipe the labels or lift them?
To contribute with something, I have a spare button that is quite yellowish, and it still have its labels on it. I will try the Hydrogen Peroxide treatment and will post the results on the photos area.
Rgrds,
FT

From how I am interpreting reading this I should have no more than 15mV at test point 418 and 419. I have 11.8 volts at each. What am I doing wrong? Do they mean must not exceed 15mV difference between the two test points?

/g/TekScopes/photo/37195/3?p=Name,,,20,1,0,0

Yes, and there's no indication of what was changed, so we don't know whether the change is "interesting" in some way. Result: ignore.

Hello, to excuse my English this is a translation .j have an oscilloscope
tektro on 2235 which n has not to work since a moment and he(it) does not
hold the avec track the trigger on a wave squares, would have you one ideas
or to look with the textbook(manual worker)

Very Thank you.?

Le dim. 11 mars 2018 à 16:37, Colin Herbert via Groups.Io <colingherbert=
[email protected]> a écrit :

Hi,
It would seem that only an Operator's Manual was produced for this
plug-in. One source that I could find for this manual is:



Good Luck.

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
brasscat
Sent: 09 March 2018 21:14
To: [email protected]
Subject: [TekScopes] Tektronix 067-0657-00Normalized Ramp Gen -
Information Wanted

Well, I dug this out of my heap of stuff. I find on Tek Wiki no more than
what what is printed on the front of this plug-in. It's a 7000 series
calibration Fixture.

Does anyone have a manual for this unit? Many thanks, Stan KO6YB




--

Patrick

I've got a problem here and hope someone could help with:
There is ( among other supply voltages ) -8.6 V DC getting out of the power supply and -8V DC returning to the same regulatory circuit ( this corresponds tp page 306 of the manual ) . My problem is that the voltages are 1 V below when the load board ( main A 10 ) is connected . When main is disconnected voltages are fine. I'm trying to figure it out is it that the main board is drawing too much current or the current limiter in the circuit is not working correctly and is limiting the current causing the voltage drop. According to the manual the current limiter should start at around 3 A ( page 142 of manual ). When I connect my DC power supply directly to the main board and setup the input voltage at -8.6 V I do get return voltage of -8V with the current draw of 2.5 A. There are 2 ICs ( U350 and U 450 ) CCD/Clock drivers - each one takes 1.1 A and the rest of the board is 0.3 A.
Does anyone know if the current consumption numbers for main are correct or too high or if anyone uses 2440 and can check the current draw of the good working scope that would be highly appreciated.

Thank you

On 14/03/18 23:56, lop pol via Groups.Io wrote:

I worst part of my 485 experience was that the labeling wiped off with just plain dish soap and water.

I had that happen with IPA, but it is probable that the IPA had absorbed some water.

The least bad (but still very unsatisfactory) replacement I've found is transparent Dymo Letratag tape.

I'd like to find a good solution to this for other reasons, in particular my ancient HP keyboard is becoming hard to read and I'd like to remark some of the letters. I tried a spray-on satin varnish from a craft shop, but it only lasted days before becoming sticky.

Hi guys. I am new to this forum, and am starting off with a wanted ad, I hope nobody minds.

I have a? 212 'scope which I bought nearly 20 years ago. The batteries were quite dead, so I removed them, and the charging circuit, and wired in a socket for a 12v external battery.

However, I have now obtained enough cells of suitable type for new battery packs and want to reinstate them as before.

When I removed the original packs, I turned two insulating posts as dummies to maintain the scope's physical integrity. Now I will NOT have thrown away the empty packs and the short cable interconnects, but repeated searches have failed to locate them.

Does anybody have an old 212 battery pack, with or without contents and connecting leads I can get my hands on?

Les.

On 12/03/18 01:10, woody wilson wrote:

C1130 has high frequency alternating voltage flowing through it, thus for long term reliability it should be a non polarised type. As per installing higher voltage rated capacitors, the higher the voltage rating the better. The only difference is size and cost.

The key distinction between polarised and non-polarised capacitors is that a polarised capacitor should only have a positive voltage across its terminals.

Thus a polarised capacitor with 18Vpp and 10Vdc is OK (voltage range +1V to +19V), but 18Vpp with 5Vdc would not be (voltage range -4V to 14V).

All other things being equal, you could use a non-polarised capacitor in place of a polarised capacitor, but it would be very large and very expensive.

As for ESR and voltage, there is not much correlation; you have to RTFDS for the specific capacitors.

I have a tek 214 with a bad crt , blown heater , dose anyone have a crt that they are able to part with ???, thanks .

Sent from Yahoo Mail on Android

Hello
Thank you for welcoming me to your home.
I am French and I have a breakdown on my tektronix 2445B.
A capacitor of the smoke supply as well as a resistor.
For the capacitor no problem but for the resistance m, impossible to read the value !!
Do you have an idea ????

I am new on this group and I can not put a picture to show you the capacitor and resistance incriminated !!!
The capacitor at the input of the power supply is 0.068microFarad X2 and 250v but the resistance ????

Bonjour

Hello

Thank you for welcoming me to your home.

I am French and I have a breakdown on my tektronix 2445B.

A capacitor of the smoke supply as well as a resistor.

For the capacitor no problem but for the resistance m, impossible to read
the value !!

Do you have an idea ????



--
Patrick