?

Isn't this just a regular nema 5-15?
<>


ST

On Thu, Feb 14, 2013 at 12:20 PM, Pa4tim <fredschneider@...> wrote:

An other question, the P6046 diff probe amplifier powersupply has that weird old USA type connector ( it is a 230V version) Like on the 547 scope and the sockets in my 515 mobile, tek 130 ect. I thought that was a rather old system but those probes are not that old so it looks like it is still in use. Is there a name for those sockets so I can buy some to make some cables and an fixed socket on my bench ? The probeamps I can plug in my 515 mobile sockets ( not handy because of the distance because I want to use them on other scopes)

. Here you se the psu, there is a big round pin too but that is out of sight,

Fred PA4TIM

For the gaussian response, the bandwidth = 0.339 / rise time which is
usually shorted to 0.35. For a sampling oscilloscope where the
response is decided weird and not gaussian, the bandwidth = 0.442 /
rise time or bandwidth = 0.468 / rise time depending on how it is
calculated.

Flat response DSOs could be anywhere from 0.4 to 0.5 but also display
preshoot and overshoot when the input pulse is too fast. I now
believe that explains the pulse distortion I saw on the Tektronix
MSO5204 that I evaluated.

?

> So if it does not start you should have a ground impedance problem ( or is it not the right test for modern groundfault breaker circuits ( those things in cabinet where your powerlines enter the house) i believe in old houses and some countrys they do not have them)

Correct - it is not compatible with precisely those. In "old" wiring, where there was a simple fuse-box there would be no problem. But in modern cabinets (ie any time in the last 30-odd years), it takes out the breaker. Turn the A6901 on and bang! Everything gets turned off.

> But if you have the manual, would you mind making a scan for me ? ( the operation part is most important)

This weekend is a possibility. What language? There are English, German, French, Spanish and Japanese operation sections. Service information is in English only.

Craig

?

OK - the manual makes no mention of a scope - it always says "load" or "

So like any piece of equipment, it is important to read the manual.


Craig

Hi Steve,

I bought it out of curiosity. I thought it might be an early prototype.
He also had something else that I thought Tom Rousseau would find
interesting:
7A26 DUAL TRACE AMPLIFIER SERIAL NO. NUMERO UNO

-UNO-COLLECTORS-ITEM-RARE-/271147508127?pt=LH_DefaultDomain_0&hash=item3f21a
6a19f

Dennis

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf
Of Steve
Sent: Wednesday, February 13, 2013 2:52 PM
To: TekScopes@...
Subject: [TekScopes] Re: Type M01 'scope?



--- In TekScopes@..., Jim Reese wrote:

Close to a 7504 or 7704. Early prototype?
?
Jim

Probably an engineering "hack" that needed most of a scope to test something
else, or a production test fixture. The front panel looks like it was
actually anodized with the lettering, so it might have been a production
test fixture that they needed more than one of.

The seller is from Portland, so either they worked at Tek, or bought it from
the company surplus store. These sort of test fixtures and engineering
hacks showed up in the store often 20 years ago.

- Steve




------------------------------------

Yahoo! Groups Links

?

Joe -

Not sure why I didn't think of that. I have a hammer that the handle
cracked on near the head. Being cheap, I wrapped the break with a flax
string that we used to make bow strings. Then I covered it with something.
Maybe lacquer. Forty years later the hammer is still in great shape.
Thanks for the idea.

Dick

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf
Of joe.knobtwister
Sent: Wednesday, February 13, 2013 5:52 PM
To: TekScopes@...
Subject: [TekScopes] Re: 475 Fan Motor

Richard:

Not sure what the split hub on the impeller looks like, but I have repaired
such things as follows: First glue the split halves back together with thin
CA (super glue) as you suggested. Then tightly wrap the OD of the hub with
heavy cotton thread, one layer will usually do. While holding the wraps
tight, saturate the thread with the thin CA. Have some acetate handy to
unglue your fingers from the thread, impeller, each other, etc. By the way,
cotton thread works best because it readily absorbs the CA, and be sure
everything is free of oil, etc. before you start.

I did do a lot of snooping around before I posted. I found information on muffin fans, R/C motors, etc., but nothing specific to the 475 motor. Maybe in some very early posts?

I took the impeller off, and got some lubricant on the shaft. The motor is fairly quiet now. Not perfect, but livable. The impeller is the problem. It is split right through the shaft hole on both sides, so it is not possible to tighten the impeller on the shaft. Are impellers available anywhere?

It looks like getting the motor out, and removing the circuit board on the back end to access the rear bearing is not a real easy job.

Dick



--- In TekScopes@..., "Tom Jobe" wrote:

Richard,
Do a search of the Tekscopes message archive on 475 fan, 465 fan and 4xx fan. This subject has been discussed many times. In my experience there is almost no chance you can't save it fairly easily. Getting oil into the sleeve bearings and setting the armature end play is about all you need to do.
tom jobe...

?

--- In TekScopes@..., "fred" wrote:
>
> I have one, can anybody tell more about it. I can not find a manual and the info I do find is confusing.
>
> I know it should be used between scope and mains but I read
> - it floats the scope and switches off the power if there is > 40V ground difference
> - it grounds the scope but over 40V it beeps as warning and then floats the scope.
>
> I use a huge variac and isolation tranfsormer to connect the instruments I'm repairing. I wanted to use this instead in some cases so it is still save but I know when there is a problem ( for instance leaking netfilter caps or transformer)
> And in other cases/experiments protect for instance a signal generator or scope . So it's original use.
>
> Fred PA4TIM
>

In the fault trip mode, it does not float the scope - it grounds it!!!!

I have never figured this thing out. and I can see as a real source of danger if used incorrectly.

It basically floats the ground of the scope up to 40 volts, and also has a GFCI detection circuit in it. The ground pin of the scope power cable is isolated, but by the open contacts of a heavy duty relay. If the GFCI trips or the floating voltage exceeds 40 volts, the relay closes, clamping the scope to ground. The power to the scope is also cut.

If you are only trying to break a ground loop in the measurement set-up, then this may be useful. For example, when an AM503 is used in the vicinity of high currents (such as motor drives using an A6303 probe), the ground loop formed between the safety grounds of the TM500 mainframe the AM503 is in, the scope ground, and the ground of the BNC cable that connects the amp to the scope input can make the measurement impossible.

Bur if you were really making a floating measurement in a high current low voltage system, tripping the protection relay could be a disaster. Shutting down the power to the scope, but not the DUT does not correct the dangerous situation. The current would be only limited by ground impedances or any over current protection in the DUT. This could be hundreds of amps. If it is a probe, then it would be the weak link and the cable would probably melt. But if it is a solid coax cable with BNC connection to the scope, who knows what would melt. For sure it would be a fire hazard.

I was at a customer site and saw a similar accident, although the A6901 was not involved. They were measuring small amplitude noise on a low voltage power supply for a computer. It had several hundred amp capability. They did not have a differential amplifier, so them measured single ended. The scope was floating, but only to a few volts. Something faulted and grounded the scope, perhaps another BNC connection. Anyway, I smelled a strange odor and turned around to see the vinyl jacket of the Tek probe lead softening and dripping to the floor. It was weird, as the entire probe cable was melting, and the insulation was dripping from the entire length. The engineer hit a panic button that killed the entire bench power. The DUT and the scope lived, but the probe was toast.

- Steve