开云体育

Hi Chuck,

While I was reading your comment to Jamie, I note with interest your suggestion that a 5AR4 is of little demand.? This tube number jogged my memory, and I found it easily in the Service Manual for my HP 200CD Signal Generator, where it is employed as a rectifier tube... I'm hoping that you're right about that, because I could use one for a spare. ;)

Phil

Dale, we use Mini Circuits HAT series attenuators DC-2GHz, $10 ea, highly recommended

Better than the old TEK parts.


Jon

Hello all curious about NVRAMs data.

Do the 2456B NVRAM images differ for various options eg 06, 09 GPIB, WR, CTT?

Or for different serial number ranges?

Or perhaps NVRAM images are same for all scopes of a type?

In other words are the options and serial range pre- stored in the NVRAM?

Many thanks


Jon

50 Ohm 2 watt attenuator, with a male BNC on one end, and female on the other.? Can be plugged into a scope input. The one's I've seen are about 2" long and roughly the diameter of a Sarpie marker pen.
Use Google images if for a visual.
Regards,Vern
On Sat, Aug 31, 2019 at 1:53 PM, Dennis Tillman W7PF<dennis@...> wrote: Hi Dale,
I have no idea from your post what it is since I don't have any way to find
out more about this part number.
I'm sure I'm not alone.
I think you would improve your odds of getting a reply from someone who does
have one if you provided a description of what it is, what it is used in,
what it looks like, and any other details you have for it.
Also, since you mention that $60 is too much, what are you willing to pay
for one?

Dennis Tillman W7PF

Hi Dale,
I have no idea from your post what it is since I don't have any way to find
out more about this part number.
I'm sure I'm not alone.
I think you would improve your odds of getting a reply from someone who does
have one if you provided a description of what it is, what it is used in,
what it looks like, and any other details you have for it.
Also, since you mention that $60 is too much, what are you willing to pay
for one?

Dennis Tillman W7PF

Hi all,

I am looking to the group for suggestions/recommendations as I am in the market for a decent DSO. I currently have a TLS216, in fine condition, without probes (therefore not useful at all). Is this unit worth holding onto and gathering up probes for this unit or would it make more sense to move on to another unit with conventional BNC connectors, for ease?

Thank you,

CJ

Would anyone have a Tektronix 011-0069-02 attenuator for sale at a reasonable price? I see them online for over $60 with shipping, but that is a bit too spendy for my pocket.
--
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA

Good morning,

Does anyone have a 555 or 556 oscilloscope they would be willing to sell? I can take a road trip to pick up if you live within roughly 800 miles of Minneapolis, so any of these states:

WI, ND, SD, IA, IL, MI, IN, or NE

Non-working is fine, I'm just interested in working on building my queue of 500 series projects for learning and restoration work.

After a 30 year hiatus from the boatanchor hobby to work on family, career, it's finally time to buy some of the things I have drooled over for a long time and picking up where I left off.

Thanks!

For sure Michael.
Big oaks from little acorns grow !!!!
Good idea of yoyurs to post that photo, it help me a lot as none
of the information I had listed or showed placement of those components.
When I have more time I will go over it again and probably change out the
other 2.2uf caps in that part and also other Tants, have a collection of
25/35/50 volt ones so should be ok.
It was fun, and nice meeting you.
Take care mind how you go
Thanks
Jim

On Sat, 31 Aug 2019 at 17:19, Michael W. Lynch via Groups.Io <mlynch003=
[email protected]> wrote:

Jim,
Great News! One never knows when one small component will completely
disable an instrument. Proving that every part is important, even critical
to proper operation.

Michael Lynch 479-226-0126 Home Phone479-477-1115 Cell
Phonemlynch001@[email protected]@...


On Saturday, August 31, 2019, 10:30:21 AM CDT, James R. Bartlett <
james.r.bart@...> wrote:

Hi Michael.
Latest update.
Scope is working again.
Changed C963, replaced R963,.
Had to readjust the pot,for the + 50 voltsupply, as +15 was showing +18,
Trace seems reasonable and all controls appear to work.
Probably needs a good going over but the main thing is it is working.
Many thanks to yourself and others who came up with various suggestions.
Hope you have a nice weekend and enjoy Labor Day.
Again thanks for all
Regards
Jim
In the land of the Leprechauns ?


On Fri, 30 Aug 2019 at 20:20, Mlynch001 <mlynch002@...> wrote:

Jim,

I will post this picture in the archives. someone else may have the same
issue with their 475.

--
Michael Lynch
Dardanelle, AR

Jim,
Great News!? One never knows when one small component will completely disable an instrument.? Proving that every part is important, even critical to proper operation.?

Michael Lynch?479-226-0126 Home Phone479-477-1115 Cell Phonemlynch001@[email protected]@...

Hi Michael.
Latest update.
Scope is working again.
Changed C963, replaced R963,.
Had to readjust the pot,for the + 50 voltsupply, as +15 was showing +18,
Trace seems reasonable and all controls appear to work.
Probably needs a good going over but the main thing is it is working.
Many thanks to yourself and others who came up with various suggestions.
Hope you have a nice weekend and enjoy Labor Day.
Again thanks for all
Regards
Jim
In the land of the Leprechauns ?

Gerry,
thanks .The ( very good ) reference link talks about the "pull the knob" to engage the delayed sweep friction "clutch" and the spring which pulls? / holds it back in "normal " position.?

I have a feeling I accidentally? glued the spring so it cannot move.

BUT
it looks as it is a common part to other typesof 4xx scope - the whole switch - and I should be able to replace just the "delayed sweep " part, which includes the clutch ,? to really fix it.

Of course if somebody has "spare " 464 timing board I would prefer? just to replace the whole board.

ANYBODY ???

This may be of help

Gerry

Unless specifically noted in the parts list as a sorted or matched item then yes in general any known good 12AX7 should work. Replacement in some circuits "might" require re-calibration? but this is not typical

Dave
manuals@...

--
Dave
Manuals@...
www.ArtekManuals.com

Jamie,

You can replace the audiophool gold standard tube (6DJ8) with a common 6BK7A. It's a TV tube so very little demand for them. Gain is a little higher and transconductance is a little lower but it works. Most of the scopes I pickup for free or for a few $ after being stripped are usually only missing the audiophool tubes like
6DJ8, 12AT7, and 5AR4, the rest are usually left unless you get a scavenger that wants to make sure he hasn't missed a money tube. BTW a workable replacement for the 5AR4 is a 5V4 again a TV damper tube and very little demand outside of the TV collector community.

?Chuck A

--
See Early TV at:

www.myvintagetv.com

Thanks for the alert, I try to avoid Epay. Bruce

Yes, this tube is definitely toast. It is all white inside, so it will have
to be replaced. One that the audio guys love, too: 6DJ8.

On Fri, Aug 30, 2019 at 4:04 PM Daniel Koller via Groups.Io <kaboomdk=
[email protected]> wrote:

Hi Jamie, You might also ask yourself, "do I need to replace it"? I
would only recommend replacing a tube if it is KNOWN to be bad. Tek
circuitry in particular is very conservatively designed, so it can operate
just fine even as the tube is failing. Frequently enough, when I'm
troubleshooting a piece of equipment, I'll test tubes in part of the
circuit that is working, and the tubes may test "bad" or "marginal". I
leave those in place so as not to add more problems. If the circuit
works, leave it be. When you've got everything working, then you can go
back and swap out the tubes that tested poorly so as to extend your time to
the next service interval.
Dan
On Friday, August 30, 2019, 03:10:08 PM EDT, Jamie Ostrowski <
jamie.ostrowski@...> wrote:



When a tube needs to be replaced in an oscilloscope, will matching the
tube number be sufficient, or are there other items to consider about the
tubes? For example, if I have a bad 12AX7, will any 12AX7 do, or do I have
to get one with the matching D-getter, the right plate color, etc, etc. I
look online for a 12AX7, and there are a multitude of variants listed.

Thanks for all the great info, guys. That helps a lot!

There are TWo of them, for parts, on e-bay

After almost a year of procrastinating I am trying to fix this "friction switch" / worn out problem.
For whatever reason I can move the delay sweep switch , I painted the friction surface and it does the job, sort off, but I cannot pull the knob.
If I remember right there is a spring to "pop " the switch back to normal.

Anyway - two question to the group
1. Is the "time base board" unique to the 464 or is it common to other 4xx scope?
There are nonworking scopes on e-bay I may be able to swap the timing switch to make the 464 work again.
There is NOTHING else busted on my 464 , just the friction switch given up the ghost..
2. Does anybody has broken 464 with WORKING delay sweep friction switch to sell?
Or just the board with WORKING delay sweep friction switch?

I would appreciate NOT to discuss "what is the delay sweep friction switch " - if you have no knowledge about it you cannot help me.
Hope you understand my remark.

Cheers