Re: water splashed on face of scope (TDS754C)
From the early '89's, I used to buy "ex-rental"
colour TVs. If I got a really "smoked up" set, After blowing off
any loose stuff, I would remove the chassis and transfer to
kitchen sink.
Hot water and a light detergent would get it
CLEAN. After that I took it into my boiler house (room) and hang
it up on the wall, leaving it for two or three weeks. A spray on
detergent would have brown "gravey" running off the cabinet, CRT
etc.
Never had any problems resulting from the washing.
I have done the same with a scope on at least one occasion.
The real problems come when people spill orange
juice or coffee in stuff, leave it to dry, then find the
mistake. If you spill the above or similar, wash thoroughly in
hot water then leave to dry properly before testing.
Les.
On 8/17/24 18:18, Radu Bogdan Dicher
wrote:
toggle quoted message
Show quoted text
Roy, Chuck,
Thank you for your thoughts.?
I am in Southern California, so if anything, we're dry here
in just about all seasons. What I did yesterday is
towel-absorb all water drops I could see anywhere on the
front, and let it sit some time on its face on a dry towel,
then on the bottom, then on the side, (like half an hour
each), so I'd not let water have the gravitational opportunity
to travel anywhere too far. As this?was in the early
afternoon, leaving the scope in the garage means the sun hits
the garage door (and I may have let it hit the scope a bit
through a very dusty garage window) and, if I don't turn on
the AC, temperature would rise to, typically, 28-30C. So
hopefully this was plenty of opportunity to remove any
moisture that was left after water was capillary taken out.?
I think it does indeed make sense to let it sit as much
as?possible before turning it on, and hopefully being summer
(and a very hot one, heatwave after heatwave), it dries to
normal conditions, and this turns out to be nothing.?
Radu.?
I knew a guy who would wash dusty/smoky electronic
chassis in the sink avoiding transformers and electrolytic
capacitors then dry them in an oven on warm for a few
hours.? Perhaps drying in an oven at the unit's maximum
storage temperature for a few hours would be a safe way to
remove residual moisture.
Chuck
|
Re: water splashed on face of scope (TDS754C)
Ah, this brings back some memories from when I worked for TEK as
a FE in one of the field offices.?
The service department had a wash rack where they would hose down
incoming hardware, and then bake it in an oven to be sure it was
completely? dry.? More details are sketchy, as this was back in
the 70's!
Daun
On 8/17/2024 13:18, Radu Bogdan Dicher
wrote:
Roy, Chuck,
Thank you for your thoughts.?
I am in Southern California, so if anything, we're dry here
in just about all seasons. What I did yesterday is
towel-absorb all water drops I could see anywhere on the
front, and let it sit some time on its face on a dry towel,
then on the bottom, then on the side, (like half an hour
each), so I'd not let water have the gravitational opportunity
to travel anywhere too far. As this?was in the early
afternoon, leaving the scope in the garage means the sun hits
the garage door (and I may have let it hit the scope a bit
through a very dusty garage window) and, if I don't turn on
the AC, temperature would rise to, typically, 28-30C. So
hopefully this was plenty of opportunity to remove any
moisture that was left after water was capillary taken out.?
I think it does indeed make sense to let it sit as much
as?possible before turning it on, and hopefully being summer
(and a very hot one, heatwave after heatwave), it dries to
normal conditions, and this turns out to be nothing.?
Radu.?
I knew a guy who would wash dusty/smoky electronic
chassis in the sink avoiding transformers and electrolytic
capacitors then dry them in an oven on warm for a few
hours.? Perhaps drying in an oven at the unit's maximum
storage temperature for a few hours would be a safe way to
remove residual moisture.
Chuck
--
Daun E. Yeagley II, N8ASB
|
Re: water splashed on face of scope (TDS754C)
Roy, Chuck, Thank you for your thoughts.? I am in Southern California, so if anything, we're dry here in just about all seasons. What I did yesterday is towel-absorb all water drops I could see anywhere on the front, and let it sit some time on its face on a dry towel, then on the bottom, then on the side, (like half an hour each), so I'd not let water have the gravitational opportunity to travel anywhere too far. As this?was in the early afternoon, leaving the scope in the garage means the sun hits the garage door (and I may have let it hit the scope a bit through a very dusty garage window) and, if I don't turn on the AC, temperature would rise to, typically, 28-30C. So hopefully this was plenty of opportunity to remove any moisture that was left after water was capillary taken out.? I think it does indeed make sense to let it sit as much as?possible before turning it on, and hopefully being summer (and a very hot one, heatwave after heatwave), it dries to normal conditions, and this turns out to be nothing.? Radu.?
I knew a guy who would wash dusty/smoky electronic chassis in the sink avoiding transformers and electrolytic capacitors then dry them in an oven on warm for a few hours.? Perhaps drying in an oven at the unit's maximum storage temperature for a few hours would be a safe way to remove residual moisture.
Chuck
|
Re: water splashed on face of scope (TDS754C)
I knew a guy who would wash dusty/smoky electronic chassis in the sink avoiding transformers and electrolytic capacitors then dry them in an oven on warm for a few hours.? Perhaps drying in an oven at the unit's maximum storage temperature for a few hours would be a safe way to remove residual moisture.
Chuck
|
Re: water splashed on face of scope (TDS754C)
Hi Radu:
I've got some scopes left out in the rain (I think on the guy got them from a dumpster.)... Anyway, when I was powering them? on, and checking them out...they appeared dry at the time. I only found out later, when I opened a top pouch, that the owner's manual had evidence of water damage. And, they had been rained on.
Anyway... nothing happened, when I powered them on.... and they seemed fine...with minor stuff, like noisy pots.
But, I believe... they had an opportunity to dry out, in the sunshine.
?
It your TDS was mine. I would have drained it... dried it off as much as possible, and then put a portable fan on it, exposing the different sides, periodically, for a day or so. Even better, if you have low humidity inside, due to air conditioning, or otherwise.
?
Then, on a hot dry day, with low humidity, and lots sun, I would put it outside. Not in the direct sun, but covered by something like a piece of plywood. You don't want the sun directly on it, since the temperatures, and the amount of heat, developed, can cause damage.
?
When it happens to me, I don't power it up.
I tend to let something that got water into it... 'dry out' a long time.
Usually the 'long time' is because I have to do a bunch of other stuff... I forget about it... and don't get around to 'working' on it again, for a significant amount of time.
I think giving it time to 'dry' is a significant factor... and perhaps a long time isn't necessary... but giving it 'time' doesn't hurt as much as letting the smoke out.
|
Re: Tek/HP/Etc Discord info
Mine said "Accept Invite" when i clicked it it said unable to
Dean? On Fri, Aug 16, 2024 at 10:59?PM cheater cheater via <cheater00social= [email protected]> wrote:
It sounds like you first need to log into the account. Then, go to the
Discord app - either on mobile, desktop, or in the browser. In the
left column where all your Discord servers are listed, scroll all the
way down to the big plus sign, and hit that. Paste in the invite link.
Done.
On Sat, Aug 17, 2024 at 12:02?AM DaveH52 via
<ac2gl.dave=[email protected]> wrote:
>
> I already have a Discord account so when I tried the link to log in it tole me that my ID was already taken. Now what?
> Dave
>
|
Re: Tek/HP/Etc Discord info
It sounds like you first need to log into the account. Then, go to the Discord app - either on mobile, desktop, or in the browser. In the left column where all your Discord servers are listed, scroll all the way down to the big plus sign, and hit that. Paste in the invite link. Done. On Sat, Aug 17, 2024 at 12:02?AM DaveH52 via groups.io <ac2gl.dave@...> wrote:
I already have a Discord account so when I tried the link to log in it tole me that my ID was already taken. Now what?
Dave
|
water splashed on face of scope (TDS754C)
You'd think it's Friday so time to wind down, so as you do that, you stand up pushing the rolling chair against the narrow space at your bench and your large mug with cold water resting right behind you tips over, right onto the face of your project 754C which was resting down on the floor, fan side down.?
I've wiped it as much as I could with some cloth towels and paper ones too, after tilting it face down onto another cloth, so all that water would seep straight down into the dry cloth. There was water even in the wells of the inputs, which I promptly dried with a paper towel rolled thinly.?
Anything else I should worry about? Is this much less of a deal than I tend to think right now? Much more??
The scope wasn't powered or anything, of course. Just being stored on the floor.
Thank you.
Radu.?
|
Added photo album Tek 2465 for sale in Montague, NJ
#photo-notice
DaveH52 <ac2gl.dave@...> added the photo album
Tek 2465 for sale in Montague, NJ
: Recapped PS, replaced blower with fan, replaced U800 with RU800. Includes 4 probes.
|
Forgot to mention I'm located in Montague, NJ 07827
|
Dave,
You've left out your location.
Radu.
I have a 2465 that I have mostly restored for sale with 4 probes. It's been de-RIFAd, the power supply recapped, the blower replaced by a fan, and the infamous U800 replaced with a RU800v2.
It's reasonably well-calibrated and ready to use.
I'm asking $400 picked up (or could ship then add the actual shipping and insurance of around $100). I will post some pix in a little while.
Dave
|
I have a 2465 that I have mostly restored for sale with 4 probes. It's been de-RIFAd, the power supply recapped, the blower replaced by a fan, and the infamous U800 replaced with a RU800v2.
It's reasonably well-calibrated and ready to use.
I'm asking $400 picked up (or could ship then add the actual shipping and insurance of around $100). I will post some pix in a little while.
Dave
|
Re: Tek/HP/Etc Discord info
I already have a Discord account so when I tried the link to log in it tole me that my ID was already taken. Now what?
Dave
|
Hi all,
some of you know we've been running a Tek/HP/Etc Discord server for a
while now. It's meant as an alternative to the mailing lists, for more
informal chat, voice and video chat, and "water cooler talk". It can
be used for anything that doesn't quite fit any of the mailing lists.
It's gathered a colorful set of regulars and less-than-regulars.
Some recent discussions include:
- tek scope carts
- agilent 2000a/3000a firmware recovery
- electromagnetic vortex cannons
- diy curve tracer project (tube compatible)
- microprobe gov auction
- plutonium welding
- knife sharpening
- 70s analog tape process
- punch card process for configuring a modern device with graphics insert cards
We have various areas such as:
General: intros, pictures, showcase
Tech: Tektronix, HP/Agilent/Keysight, Other T&M, Electronics in
general, Audio/HiFi/Musical Instruments, For Trade & Sale, Retro
Computers, Mechanical Engineering, Gear Lists, References, BSTJ, Old
Journals And Texts, Cutting Edge
The last few (References, BSTJ, Old Journals And Texts, Cutting Edge)
are full of technical reading material spanning several hundred years.
Here's a link to join. The link will work for 7 days after which you
can request a new link off-list. There are no bots and no spam.
All welcome
|
Tektronix 577 Fraud Kleinanzeigen Germany
Hi All,
I do not know where else to post this, but there is an individual in Germany on the Kleinanzeigen Portal selling a cheap and in good condition Tektronix 577.
I have bought this, and it was never delivered.
Today I see, that the same device with same description but different seller appeared again.
Be warned, I am pretty sure, this is Fraud.
|
Re: Tektronix TDS 460A Digital O Scope power cycling
If R410 is reading open, it's probably a safe bet that it is - a resistor reading a lower value in circuit is inconclusive as there could be parallel paths influencing the reading. ?If it reads HIGHER than it should, the likelihood is that the resistor being measured is out of spec high at the very least. ?I'd start by tacking a 1M ?resistor across the questionable R410 and seeing what happens. -Pat
?
> ------ Original Message ------
> From: buma7@...
> To: [email protected]
> Sent: Monday, August 5th 2024, 04:55 PM
> Subject: [TekScopes2] Tektronix TDS 460A Digital O Scope power cycling
? Symptom:? I have a Textronix TDS 460A Digital O Scope that worked fine at last use.? Unit was unused for about 4 ¨C 6 months.? Upon power up the CRT screen lights up and the ¡°clock¡± emoji is present on the screen.? The front panel lights flash and you can hear the relays cycling.? The fan runs.? After about 10 seconds the unit goes into a cycling state, cycling on and off every two or three seconds.? Each time it powers the fan runs and the panel lights flash.? You can hear a ticking sound that seems to decrease in volume as time passes. Question:? The troubleshooting procedures decision points ask, ¡°Does the oscilloscope power up.¡±? Does the fact the unit powers up for 2 seconds repeatedly constitute ¡°power up¡±.? If it does You move beyond the Backplane board.? If it does not, you are looking at either a LVPS A25, Front Panel A06, Backplane A01, or Aux Power Board A07 failure/replacement. Troubleshooting: 1.????? Checked the voltage of the two 3V batteries. a.????? Battery to A03 CPU Assy. Read 2.04V b.????? Battery to A09 DSP Assy. Read 3.0V c.????? Reversed batteries on reinstallation.? No change in symptoms. 2.????? Verified 115V AC at pins 1 & 3 of J! on LVPS.? (Aux Pwr board to LVPS) 3.????? Performed the LVPS troubling shooting procedure (Fig 6-31 pp 6-78) a.????? Checked voltages (Table 6-11, pp 6-79) b.????? All well below spec. in millivolts.. c.????? Coming down left side all answers are ¡°yes¡± except last question (Are secondary voltages within Spec (Table 6-11, pp 6-79). d.????? Procedure would indicate that the issue is not with the A25 LVPS. 4.????? Disconnected white wire between Aux. Pwr. Board and LVPS Board. a.????? No change in performance or symptoms. Remade connection. 5.????? Disconnected plug from J2 (22 pin connector on A25 LVPS board). a.????? No change in performance or symptoms.? Remade connection. 6.????? Pulled the LVPS board from scope. a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites. b.????? Checked E caps in circuit with a MESR meter.? Seemed ok. c.????? Read something about R410 (1M).? Read it while in circuit and it appeared to be open.? Planning on removing one side from circuit and read again. 7.????? Performed the Backplane trouble shooting procedure (Fig. 6-46 pp 6-92) a.????? Again, the question goes to what constitutes ¡°power up.¡± ????????????????????????????????????????????????????????????? i.????? If ¡°yes¡± could be issue is elsewhere. ???????????????????????????????????????????????????????????? ii.????? If ¡°no¡± could be problem with A25 LVPS, A06 Front Panel, A01 Backplane, or A07 Aux. Pwr. Board. 8.????? Pulled A03 CPU, A02 Display Assy., and A09 DSP Assy. a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites. b.????? Reinstalled all three. 9.????? Visually inspected A01 Backplane board while Ao3, A02 and A07 out a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites. ? I'd appreciate any advice, insight, and ideas on where to go from here.? For info, you are talking to a mechanical guy.? If it had oil or water leaking out or made a grinding noise I could figure it out.
? Thanks, 73 Harrison N1FAM
|
Tektronix TDS 460A Digital O Scope power cycling
Symptom:? I have a Textronix TDS 460A Digital O Scope that worked fine at last use.? Unit was unused for about 4 ¨C 6 months.? Upon power up the CRT screen lights up and the ¡°clock¡± emoji is present on the screen.? The front panel lights flash and you can hear the relays cycling.? The fan runs.? After about 10 seconds the unit goes into a cycling state, cycling on and off every two or three seconds.? Each time it powers the fan runs and the panel lights flash.? You can hear a ticking sound that seems to decrease in volume as time passes.
Question: ?The troubleshooting procedures decision points ask, ¡°Does the oscilloscope power up.¡±? Does the fact the unit powers up for 2 seconds repeatedly constitute ¡°power up¡±.? If it does You move beyond the Backplane board.? If it does not, you are looking at either a LVPS A25, Front Panel A06, Backplane A01, or Aux Power Board A07 failure/replacement.
Troubleshooting:
1.????? Checked the voltage of the two 3V batteries.
a.????? Battery to A03 CPU Assy. Read 2.04V
b.????? Battery to A09 DSP Assy. Read 3.0V
c.????? Reversed batteries on reinstallation.? No change in symptoms.
2.????? Verified 115V AC at pins 1 & 3 of J! on LVPS.? (Aux Pwr board to LVPS)
3.????? Performed the LVPS troubling shooting procedure (Fig 6-31 pp 6-78)
a.????? Checked voltages (Table 6-11, pp 6-79)
b.????? All well below spec. in millivolts..
c.????? Coming down left side all answers are ¡°yes¡± except last question (Are secondary voltages within Spec (Table 6-11, pp 6-79).
d.????? Procedure would indicate that the issue is not with the A25 LVPS.
4.????? Disconnected white wire between Aux. Pwr. Board and LVPS Board.
a.????? No change in performance or symptoms. Remade connection.
5.????? Disconnected plug from J2 (22 pin connector on A25 LVPS board).
a.????? No change in performance or symptoms.? Remade connection.
6.????? Pulled the LVPS board from scope.
a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites.
b.????? Checked E caps in circuit with a MESR meter.? Seemed ok.
c.????? Read something about R410 (1M).? Read it while in circuit and it appeared to be open.? Planning on removing one side from circuit and read again.
7.????? Performed the Backplane trouble shooting procedure (Fig. 6-46 pp 6-92)
a.????? Again, the question goes to what constitutes ¡°power up.¡±
????????????????????????????????????????????????????????????? i.????? If ¡°yes¡± could be issue is elsewhere.
???????????????????????????????????????????????????????????? ii.????? If ¡°no¡± could be problem with A25 LVPS, A06 Front Panel, A01 Backplane, or A07 Aux. Pwr. Board.
8.????? Pulled A03 CPU, A02 Display Assy., and A09 DSP Assy.
a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites.
b.????? Reinstalled all three.
9.????? Visually inspected A01 Backplane board while Ao3, A02 and A07 out
a.????? No obvious problem.? No corrosion, no swollen E caps, no burn sites.
?
I'd appreciate any advice, insight, and ideas on where to go from here.? For info, you are talking to a mechanical guy.? If it had oil or water leaking out or made a grinding noise I could figure it out.
Thanks, 73 Harrison N1FAM
|
Re: Tektronix 585 Restoration
The voltage at all four of the vertical deflection plate terminals should be about 280V. The voltage on both deflection plates should be the same or the beam will be deflected away from the center of the screen. The vertical deflection amp is differential so that you should see nearly the same voltages on either side as you move up or down through the amplifier stages, except that the signal portion will be inverted from one side to the other If you need 7788 tubes, some tv stations might have one stored away somewhere. They were used in some television waveform monitors.
Hugh Gilbert
I¡¯ve checked and triple checked all that. I have 321v and 300v going in on the ¡°terminal resistor¡± pins and 321v and 300v coming out of the two vertical pins, blue/white 300v and brown/white 321v.?
|
Re: Tektronix 585 Restoration
I¡¯ve checked and triple checked all that. I have 321v and 300v going in on the ¡°terminal resistor¡± pins and 321v and 300v coming out of the two vertical pins, blue/white 300v and brown/white 321v.?
|
Re: Tektronix 585 Restoration
I would look for things that you could have done wrongly in installing the new CRT. For instance, deflection wires swapped, RFC's broken, or poor contact to the deflection pins. Unlike the horizontal pins, the vertical pins actually pass current, so the contacts must be good. And, there is a connection on both ends of the vertical deflection plates.... to pass that current. -Chuck Harris On Sat, 03 Aug 2024 14:29:24 -0700 "Eric Boyle via groups.io" <k0elb@...> wrote: Well, remove the blue/white wire from V1274 to the CRT and I get a
half trace sweep. Unhook the brown/white wire from V1284 and I get a
dot. Swapping the tubes from one socket to another makes no
difference.
|
DaveH52
Cubdriver
Eric Boyle