Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- TekScopes
- Messages
Search
|
Re: Dead 7603
Thanks, everybody, for your help. Here's where I am now: Primary not
toggle quoted message
Show quoted text
open; it measures about 3 ohms with the on/off switch on (obviously open with it off!). Poked around P1171 and measured DC voltages. -50V, -15V, +15V, +50V, and +130V all within spec. +5V measured 4.46 V, when it's supposed to be 4.85V minimum. Hey, the power light is lit now! Must have been a bad connection that I reconnected when moving the power supply section back into place. Checking ripple and looking for shorted tantalum capacitor(s) on the +5V rail next. Jim ------ Original Message ------
From: "Vintage Test via Groups.Io" <mel.purcell@...> To: [email protected] Sent: 6/29/2018 7:31:36 AM Subject: Re: [TekScopes] Dead 7603 Hi Jim, --- This email has been checked for viruses by AVG. |
|
Re: MEDIA MAIL (Re: [TekScopes] I have two Tek manuals I don't think I need)
David, they absolutely don't want to offer it.
toggle quoted message
Show quoted text
I just mailed a book (a user guide for a camera) to a friend. The counter agent was funny. I handed the package over and said "it's a book and it should go the cheapest way possible." I didn't mention "Media mail" mostly as a test after seeing Dave's comment (I usually write media mail on the package before I even go to the post office.) The fellow tells me about the priority mail and First class prices.... I smiled and said "wow, that's expensive for a book... (long pause) but I didn't hear you mention a 'media mail' price?" Him: "Oh, sorry, just one second, let me look that up for you" I could see the screen in a reflection and the price was right there.... The cost was something like $3.17 (or less) instead of $11 to $17. I get that they want to be as profitable as possible, but I think they need to do that through efficiency and not by overcharging the customer and directing them away from services that were designed just to benefit certain kinds of mailings. They'd be far better off to charge a 1/10 cent more for junk mail than push retail customers to high priced services that make them choose UPS or some other service. Grant On Tue, Jul 3, 2018 at 11:05 AM, Vince A <vince83687@...> wrote:
David |
|
Re: SC504 Gain Knob Removal
tom jobe
Hi Larry,
toggle quoted message
Show quoted text
Your question got me wondering about this, so I took the side cover off of an SC504 to have a look. The service manual mechanical parts diagram shows the knob has a longer part that goes back into the Channel switch so I looked to see if there was a screw or other fastening device back inside of the scope. I removed the plastic rod that goes through the knob assembly by disconnecting it at the aluminum collar on the VAR switch, and then the knob just fell out for some reason. I put the knob back in and then it would not come out again. So I nervously pried and pulled and got it back out again without damaging it. A study of the knob shaft showed no locking mechanisms of any kind, so I rubbed a very thin smear of Johnson's paste wax on the knob shaft extension and put it back in. After that the knob slid in and out nicely and the only thing holding the knob in is the 1/8" fiberglass VAR shaft and small VAR knob in the center of the knob in question. I guess the knob was just stuck from being in there for 30 or 40 years plastic on plastic? Do be careful about a very thin aluminum washer that is on the knob's rear shaft extension, as it would be very easy to drop that washer into the scope. My guess is that this washer is part of the spacing arrangement that keeps the lettering on the back side of the knob skirt from hitting the front panel and getting damaged, and it also might keep the two plastic parts from rubbing on each other at the knob extension / attenuator surfaces? tom jobe... PS I wonder if one drop of water could be put in from the side where the knob shaft extension goes into the attenuator assembly to break it free as you wiggled the knob to spread it around? You would want to be very careful about anything you put in there, as the short and long term effects on the plastic parts could be devastating. On 7/6/2018 11:30 AM, Larry McDavid wrote:
I have a SC504 scope module with a damaged Channel 1 knob skirt and I have a Tek replacement skirted knob. I can remove the small red central knob by loosening a set screw. |
|
Re: 114xx bezzel buttons
This is the issue
toggle quoted message
Show quoted text
On Fri, Jul 6, 2018, 4:13 PM Pete Lancashire <xyzzypdx@...> wrote:
I didn't look at text website for service information do you have the URL |
|
Re: 114xx bezzel buttons
I didn't look at text website for service information do you have the URL
toggle quoted message
Show quoted text
or can I just type in 11403 ? On Fri, Jul 6, 2018, 3:39 PM <jbau@...> wrote:
Not sure exactly what your question is, but I've removed the panel/trim |
|
Re: Questions about TM mainframes with Option 2
You have some conflicting terms.
The 5Axx modules are 5000 series oscilloscope amplifier plugins. They are not compatible with the TM500/TM5000 series mainframes. The AM502 is a TM500 plugin. It is not compatible with the 5000 series oscilloscopes. Some TM500 plugins are not compatible with the TM5000 series because of power supply issues. There are only a couple of these and they are listed in the manuals for the TM5000 series mainframes. Most of the TM5000 series plugins are not compatible with the TM500 series mainframes, but there are some exceptions to this as well. For a given TM500/TM5000 plug-in, the manual will have a section on the rear interface connections. Any connection listed there can be wired to a rear panel BNC or Dsub connector on the Option 02/Option 12 mainframes. Sometimes you must move an internal jumper in the plug-in to route the signal to the rear interface instead of the front panel. It's all in the manuals. Dave Casey On Thu, Jul 5, 2018 at 5:49 AM, PHB via Groups.Io < mole_org@...> wrote: Hi all, first post here. |
|
Questions about TM mainframes with Option 2
PHB
Hi all, first post here.
I'm looking to set up a TM 5000 series mainframe and trying to sort out the compatibility gotchas before I "pull the trigger" on one of these. My main interest is in the differential amplifier plugins. I do mostly audio work and these are the ones I am thinking about: 5A13 5A19 5A20 5A21 5A22 5A26 AM502 Question #1) Will the AM502 work in a 5000 series mainframe? (there seems to be conflicting information about whether or not 500 series plugins work in 5000 series mainframes) Question #2) If I get a 5000 series mainframe with Option 2 (w/ the BNC connector panel on the back of the unit), would I be able to wire from an A5xx plugin's single ended output to a BNC connector on the back panel, and then connect this to a standard o-scope input? My understanding is that Tek 5000 series scopes' baseline sensitivity is 10 mV/division, so I'm assuming I can set my scope to 10 mV/division, hook up the BNC out (wired to the A5xx plugin's output) from the back of the TM 5000 series mainframe and just plug it into my scope. Does this sound right? I really appreciate any advice you have about this. |
|
Re: MEDIA MAIL (Re: [TekScopes] I have two Tek manuals I don't think I need)
Vince A
David
toggle quoted message
Show quoted text
You got to be vigilant at the PO, know before you go! Google and asking questions here really helps you out. If it sounds fishy go back another day or see another PO. Use a different guy/girl on another day at the PO. Vince :) --- -vince :") Thank you for your reply Got computer troubles, We have the answers! Visit Starlite Systems Starlitesystems Dot Com My other computer cost's $35.00. Ask me about it On Tue, Jul 3, 2018 at 9:13 AM, David Berlind <david@...> wrote:
So, just fyi.. I went back to the PO and asked "What about the media mail |
|
Re: DC 508
The option 7 on the DC508 increases its value as it allows it to work with the TM500 series tracking generators. If it has option 1, the oven oscillator, that also increases the value. The oven oscillator is a silver box at the rear of the PCB, easy to see if it is there.
Also, you do not need to be a HAM operator to play with the old test equipment. You do need a HAM license if you want to build transmitters for the HAM bands, no license needed for receivers and other gear.. |
|
Owon SDS7102 Deep Memory Digital Storage Oscilloscope
Vince A
Morning Gentleman
Well I finally bit the bullet and bought a 100mghz Scope. Now I need to learn how to use it. :) Is there a oscilloscope for dummies book out there or just some quick pointers you guys would like share with me? I am sure a'll have a LOT of questions but I don't have a clue what to do next and what all the fancy controls could or should do for me? I am mostly into vacuum tube audio and some solid state electronics. The package did come with some really nice probes and almost like a very small jewelers type of screwdriver driver? And Manuel What I would like to do first with this is to measure the Pre-amp signal of the 12AT7 to see if i am getting a clean signal to the output of my first pair of 6L6 tube amp I built using Russian output tubes. And if not, how could I clean that up by doing other things to get the signal better though the path? I don't learn very well by reading books guys, I am more of a hands on guy. When I read books, the pages melt into each other after about 2 pages. So reading online is much better for me. That is why I like the combined knowledge here. How did you guys learn how to use a Scope? How did you go about getting familiar with a Scope? What was your very first Scope? This is my VERY first Scope of anything guys. Thanks loads Vince :) --- -vince :") Thank you for your reply Got computer troubles, We have the answers! Visit Starlite Systems Starlitesystems Dot Com My other computer cost's $35.00. Ask me about it |
|
TDS744
Vintage Test
Hi All,
I've just laid my hands on one of these for a decent price, knowing it didn't work. The owner said it worked one day and jus did tick, tick etc the next - a familiar story! When I stripped it, I found a load of duff diodes/transistors and two-way devices in the standby circuit, which I replaced. I powered it up - still the same, except that the front-panel LEDs all flashed too now. On a whim, I disconnected everything from the processor board, and lo and behold -it powered up and worked properly into a VGA monitor. Now, to the problem; the CRT driver assembly is clearly faulty, but there's no schematic for it anywhere. I have the manual for TDS540, which has a lot of similarities, but is monochrome and not colour, so the CRT driver assembly is way different. Do any of you happen to have any experience with these 'scopes? Cheers, -- you can never have enough oscilloscopes, DMMs, valve testers or soldering irons . . . |
|
Re: Dead 7603
Vintage Test
Hi Jim,
On a 7603 - and I've sorted a lot of them - the main culprits of no power-up, when you've checked all the usual suspects, is the power supply filter capacitors. To check these, you will have to remove the raw voltage power unit, situated at the bottom rear of the 'scope. There are three large cross-head screws on each side of the chassis, which allows you to carefully draw out the mains transformer and attendant rectifier/capacitor PCB. If the capacitors are all metal cased, it is likely that these are faulty now and need replaced. Looking at the rear of the 'scope, there is a rectifier attached to the bottom left corner , underneath the PCB. This is the +/- 15V rectifier and the two caps nearest the left edge are the reservoirs. If these don't have about 24V DC on them, then nothing else will work. Have a look at this and get back to us. -- you can never have enough oscilloscopes, DMMs, valve testers or soldering irons . . . |
|
Re: Kludging together a TDR or similar?
hi guys, thanks for the replies.
I don't have the parts necessary to build a pulser. Can I use the mainframe's pulse generator? The cable goes from a local distribution box, part underground, part overground, and then goes to a wall socket used only by my modem. There is no splitting and no neighbors using this. The run in my yard that is overground is maybe 30m at most. There was no thunder when this stopped working, just heavy rain. On Fri, 29 Jun 2018, 06:53 Michael A. Terrell, <mike.terrell@...> wrote:
|
|
Re: 2215 avoiding future CRT damage
tom jobe
Thank you Hakan!
toggle quoted message
Show quoted text
That is an excellent test that will probably work on other scopes to get an idea if the CRT is good. Your contributions to Tekscopes are always good, and usually you are the only one on the planet that has the information you post. tom jobe... On 7/6/2018 11:08 AM, zenith5106 wrote:
So my CRT / filament is cooked then, by now, after nearly 40 years of use...At the time we had a simple procedure at our Field Office to determine |
|
Re: 2215 avoiding future CRT damage
On Fri, Jul 6, 2018 at 11:08 am, zenith5106 wrote:
We set the T/B to the fastest sweep speed withOK... just perform said test, here is the result : /g/TekScopes/photo/62323/0?p=Name,,,20,1,0,0 I adjusted the ISO setting of the camera so that the brightness on the pic actually matches the brightness level that my eyes perceive. That's under normal conditions : a couple fluorescent tubes above the bench for lightning, and me sitting right in front of the scope, at a close but reasonable distance, I mean I did glue my face to the screen... Looks like an "acceptable" tube then ? I mean it's very difficult to see, and any dimmer than this, would make it invisible but... as you say, you can still see the trace. Plus, if I turn the var hold-off to the min, brightness comes back to normal, the trace becomes perfectly visible, no effort needed whatsoever. I will admit I don't really master the var hold-off feature, I am not sure I get why it impacts the brightness level.. but obviously it does. Will need to do some reading and experimenting ! ^^ Anyway, looks like my CRT is not worn out in the end, what do you say ? That's good ! :-) I mean I have sooo many problems left to fix on this scope, I really didn't need yet another (costly ! ) problem on my list ! LOL Regards, Vincent Trouilliez |
|
SC504 Gain Knob Removal
I have a SC504 scope module with a damaged Channel 1 knob skirt and I have a Tek replacement skirted knob. I can remove the small red central knob by loosening a set screw.
How is the skirted knob removed? I've tried gently pulling on it without success. The knob has a long plastic shaft with some internal ribs to fit over another shaft but I don't know how the knob is attached. Anyone done this? -- Best wishes, Larry McDavid W6FUB Anaheim, California (SE of Los Angeles, near Disneyland) |
|
7A13 Comparison Voltage coarse knob
I have a later model 7A13 with the LED volts readout. It has the serial # 104748 and was made in Guernsey. It works fine, but the Comparison Voltage coarse knob is not the correct one. Would anyone have one of these to spare? Being where they are located, they are pretty vulnerable to damage and so may be a bit rare (hence the silly prices sometimes quoted). The Tek part number for the knob is 366-1084-00 and it just may be used on some other item of equipment. Reasonable costs understood.
TIA, Colin. |
zenith5106
Vince
to navigate to use esc to dismiss