Re: 465 Missing a Few Components
Thanks for the tip Dave. ¡° /g/TekScopes/photo/262670/0?p=Created,,,50,2,0,0¡± Let¡¯s see if that works. I¡¯m definitely going through and check all the solder joints. Some look quite cold...
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Re: 465 Missing a Few Components
On Mon, Apr 5, 2021 at 10:45 AM, Raymond Domp Frank wrote:
On Mon, Apr 5, 2021 at 11:23 PM, Stephen wrote:
It¡¯s a European made scope, so the serial number starts with 70xxxxx.
Actually, Tektronix had factories in three locations in Europe:
Units with serial numbers starting with 1 were made in Guernsey (Channel
Islands)
Units with serial numbers starting with 2 were made in London (UK)
Units with serial numbers starting with 7 were made in Heerenveen
(Netherlands)
Unfortunately, there is no way to cross-reference serial numbers between
factories; each used their own serialization.
Have a look for the main board number; it should have the form of 670-xxxx-yy
and is usually located near the Beam Finder switch.
Raymond
Indeed. I also found that, European made models are often closer to higher serial numbers in the US. Board serial number is GC-2773-06. That¡¯s all there is that I can see. /g/TekScopes/photo/262670/0?p=Created,,,50,2,0,0 If the link doesn¡¯t work, scroll through the pictures. Also, that resistor and solder joint next to it, don¡¯t look to good. They seem to have been to hell and back...
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Re: 465 Missing a Few Components
On Mon, Apr 5, 2021 at 11:44 PM, Dave Peterson wrote:
The early 465s don't have a mesh in the tube according to my SMs.
Oh yes, they definitely do. I don't know if my SN<250K does or doesn't.
So yes, it does. The mesh not only increases the CRT's deflection sensitivity, it unfortunately also increases the spot size. A lot of development has been done after these first efforts. Later versions of the 465 used modified CRT's, resulting in slightly sharper traces. Other improvements helped that. Raymond
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Re: 465 Missing a Few Components
On Mon, Apr 5, 2021 at 10:48 AM, Dave Peterson wrote:
Uh, what? That picture link did not work. Try:
"/g/TekScopes/photo/262237/2?p=Name,,,20,0,0,0"
With quotes?
I told you. I have that problem quite often actually... Links don¡¯t always go to the intended picture...
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Re: 465 Missing a Few Components
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Re: 465 Missing a Few Components
On Mon, Apr 5, 2021 at 11:23 PM, Stephen wrote:
It¡¯s a European made scope, so the serial number starts with 70xxxxx.
Actually, Tektronix had factories in three locations in Europe: Units with serial numbers starting with 1 were made in Guernsey (Channel Islands) Units with serial numbers starting with 2 were made in London (UK) Units with serial numbers starting with 7 were made in Heerenveen (Netherlands) Unfortunately, there is no way to cross-reference serial numbers between factories; each used their own serialization. Have a look for the main board number; it should have the form of 670-xxxx-yy and is usually located near the Beam Finder switch. Raymond
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Re: 465 Missing a Few Components
That serial number just begs for restoration! One mans junk is another's treasure. I'm turning into a treasure collector. Wink. I guess it's up to the CRT. I think most everything else is still relatively replaceable, even across SNs. The early 465s don't have a mesh in the tube according to my SMs. I don't know if my SN<250K does or doesn't. I haven't traced that aspect yet. It does seem to be a hybrid of details from both before and after SN250K. I'm curious to see if the lack of a mesh has a noticeable effect on the trace. So far mine seems perfectly nice. Maybe it has one. What other significant differences are there between pre and post SN250K? I know the time/div knob and horizontal display markings are different: /g/TekScopes/photo/262237/0?p=Name,,,20,0,0,0 Otherwise I think an old scope can be restored with later parts. That's a very cool find Stephan. I am jealous. I vote for restoration, but it's not my money (or garage space). Good luck with it! Dave
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Re: 465 Missing a Few Components
The image links don¡¯t always go to the right images...
Maybe I¡¯ll restore it. That would be nice. Otherwise, well... It was a parts scope to begin with...
But hopefully, I¡¯ll restore it.
I can replace the two power transistors with TIP35C (maybe all of them), and swap B and C around, I guess. They¡¯re well overrated. I¡¯ll replace the missing parts, and take it from there.
I don¡¯t like seeing potentially reparable good pieces of gear go to waste.
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Re: 465 Missing a Few Components
Hi Dave, It has no options I can see, and nothing is mentioned on the front panel either. It¡¯s a European made scope, so the serial number starts with 70xxxxx. Actually a very early European model from the low serial number. Funny, the serial is actually xxx465!! /g/TekScopes/photo/262670/0?p=Created,,,50,2,0,0 There was definitely something in that spot, if I trust the solder mark on the board below R1549... /g/TekScopes/photo/262670/1?p=Created,,,50,2,0,0 C1549??
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Re: 465 Missing a Few Components
Of course, as soon as I send that:
I was looking at the SN > 250K manual, but the SN < 250K manual indicates that this is C1549. It was moved to near the PS test points in later revisions. Right next to the +15v test point.
This must be a very early SN < 250K scope! Fun! Any chance of restoring it?
Dave
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Re: 465 Missing a Few Components
Stephen,
I think you are right that it is Q1546. My A9 boards are not labeled, but the collector traces back to CR1541 and C1542, which is Q1546.
Does this scope have either option 4 or option 7? The board diagram in the SN>250K service manual (Fig. 8-18) indicates 3 possible capacitors with the note "2 Used only with Options 4 and 7". My boards have 3 pairs empty vias at that location, but look a little different than your picture in this regard.
I do have an empty via at the trace shown in your picture. The one that travels under the fuse to CR1569. The other via at that location - between the trace via and the R1549 via just to the right of the arrow tip - is not present on my boards. I'm looking at both a pre and post SN 250K boards. So I'm at a loss as to what that might have been. The trace is apparently the -8v rail, unless it's the ground side of CR1569, for what that's worth.
What is the SN range of this scope? Is it pre or post SN 250K? Any other options or indications of variation?
Sorry I'm not more help.
Dave
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Re: 7603 horizontal performance
It's the same animal. I have one sat here waiting for a 2465x in need of a jug.
PS it's bad etiquette to hi-jack an thread about a different subject.
David
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of durechenew via groups.io Sent: 05 April 2021 20:02 To: [email protected]Subject: Re: [TekScopes] 7603 horizontal performance As the discussion is of high interest and importance I would like to ask if anyone can confirm without a doubt that the CRT for 2465 and 2430/32/40 are the same PN? From schematics cannot say that - they are in the list but as assembly. If someone has (had) access to physical details would be great to know... A 2430 could be bought (can't be sure of real condition of CRT, but could have an idea) for $50; would make a great spare part CRT for a 2465... TT
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465 Missing a Few Components
For about 15€ I bought this 465 for parts. Seller said it didn¡¯t turn on at all. I opened it up, and indeed, it definitely can¡¯t function. There are apparently 4 missing components in the power supply. Can anyone confirm that the 2 missing transistors are Q1534 and Q1546? Q1546 is very hard to make out from the TekWiki schematic. The other, although not missing, seems to be Q1566. I did locate R1549, but not the small part that appears to have been removed as well, perpendicular to it. I think it might be a small fuse...? /g/TekScopes/album?id=262670Thanks
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Re: 7603 horizontal performance
As the discussion is of high interest and importance I would like to ask if anyone can confirm without a doubt that the CRT for 2465 and 2430/32/40 are the same PN? From schematics cannot say that - they are in the list but as assembly. If someone has (had) access to physical details would be great to know... A 2430 could be bought (can't be sure of real condition of CRT, but could have an idea) for $50; would make a great spare part CRT for a 2465...
TT
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Re: Reed relays for a sick AA501A
White browsing some paper catalogues I found a "microscopic" reed relay
measuring 8.6 x 4.4 x 3.6 mm , which might be useful as a replacement for
these failure-prone Tektronix subminiature devices.
The part number is CRR-05 , made by Standex/Meder.
This is a link to the datasheet:
I've only found a SPST variant.
Regards,
Jan
Eric <ericsp@...> schrieb am Mo., 5. Apr. 2021, 15:52:
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Show quoted text
Dennis,
I have something coming for the mechanical and pin out issues. I
will let everyone know how it goes well. I should know more by the end of
the week.
Eric
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Dennis
Tillman W7pF
Sent: Sunday, April 4, 2021 4:23 PM
To: [email protected]
Subject: Re: [TekScopes] Reed relays for a sick AA501A
Hi Eric,
I don't have an AA501A. I have an AA5001A which also uses the same relays.
Unfortunately I can't get to the board they are on without disassembling
the plugin.
I looked at the COTO relay and they look like a good choice electrically.
Mechanical issues like location and spacing of the leads will probably be
the main issue you have to deal with. The best approach might be to mount
the Coto relays "dead-bug" style with their leads facing up and away from
the PC Board. A small piece of double-back tape can be used to anchor the
relay to the PCB. Then you can wire short jumpers to go from each Coto lead
to the correct hole in the PCB.
Dennis Tillman W7pF
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Eric
Sent: Sunday, April 04, 2021 12:28 PM
To: [email protected]
Subject: Re: [TekScopes] Reed relays for a sick AA501A
Dennis,
Thanks for the info I did not know whey were this easy to rebuild.
Unfortunately these particular ones are sealed on the ends molded plastic
caps for the lead wires. There are 5 relays in the 501A that handle the
high voltage ranges. I am having issues with 60, 20 and 6. With them also
causing some havoc on auto range as well. When I have a situation where
they are working the unit locks in and works as expected. These are
supposed to have a 5Vdc coil but when I was testing one with a square wave
it would not trip till about 8Vdc. In the 501A all the relays are energized
by the output of a hex inverter then they are allowed to fall low and open.
These are energized = Closed I believe. The odd thing about these is they
are DP ST relays as they cover + and - inputs with the same relay. These
are silver packages with 4 legs on one side and 2 on the other. 2 outer
legs are for the coil the 2 inner ones are for the reeds running straight
through.
This 501A is worth saving especially this one as it has option one the
intermodulation measurements. Of course it will need a full cal after
words.
Being double pole has caused me a fair bit of grief in the replacement
department.
Eric
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Dennis
Tillman W7pF
Sent: Sunday, April 4, 2021 12:57 PM
To: [email protected]
Subject: Re: [TekScopes] Reed relays for a sick AA501A
Hi Eric,
Reed relays are conceptually simple devices in electrical and in
mechanical terms. There are only two parts - the reed- and a coil wrapped
around it. The reeds come in two types: the more common ones have normally
open contacts. The less common ones have normally closed contacts. The
coils are designed to operate on a specific voltage like +12VDC, +15VDC, or
+28VDC. Coil resistance is dependent on the operating voltage.
I have a bunch of the glass reeds I picked up somewhere 50 years ago and
every few years I find a use for one of them. The reeds themselves are
cheap and probably available on eBay for a few dollars for a handful of
them.
The only thing that matters is the diameter of the glass envelope
surrounding the reed and the length from one end to the other of the
contact pins. It is good to have an assortment of sizes to work with.
A bad reed can almost always be slid out of the coil and replaced with one
that is approximately the same size. You can't bend the leads (even
slightly) or that will break the glass. But you can cut them down to size.
You can hear the reed make and break contact (if you are in a quiet room)
to determine the reed closes BEFORE the proper voltage is applied to the
coil. For instance, a 12V reed relay should close when you apply about 8V
to it.
Dennis Tillman W7pF
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Eric
Sent: Saturday, April 03, 2021 8:25 PM
To: [email protected]
Subject: [TekScopes] Reed relays for a sick AA501A
I have a sick AA501A that I am trying to bring back from the dead. I am
wondering if anyone knows of any replacement reed relays. The existing part
is Tek number 148-0134-00. The part number on the part is EAC 2A05X250biaa.
If there is not a supply of these or if these are troublesome parts I am
looking at a possible modern replacement. Coto 2332 Mouser part
816-2332-05-010 . It
will need some adaptation of course but it does look like it will fit
physically.
Eric
--
Dennis Tillman W7pF
TekScopes Moderator
--
Dennis Tillman W7pF
TekScopes Moderator
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Re: Reed relays for a sick AA501A
Dennis,
I have something coming for the mechanical and pin out issues. I will let everyone know how it goes well. I should know more by the end of the week.
Eric
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Dennis Tillman W7pF Sent: Sunday, April 4, 2021 4:23 PM To: [email protected]Subject: Re: [TekScopes] Reed relays for a sick AA501A Hi Eric, I don't have an AA501A. I have an AA5001A which also uses the same relays. Unfortunately I can't get to the board they are on without disassembling the plugin. I looked at the COTO relay and they look like a good choice electrically. Mechanical issues like location and spacing of the leads will probably be the main issue you have to deal with. The best approach might be to mount the Coto relays "dead-bug" style with their leads facing up and away from the PC Board. A small piece of double-back tape can be used to anchor the relay to the PCB. Then you can wire short jumpers to go from each Coto lead to the correct hole in the PCB. Dennis Tillman W7pF -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Eric Sent: Sunday, April 04, 2021 12:28 PM To: [email protected]Subject: Re: [TekScopes] Reed relays for a sick AA501A Dennis, Thanks for the info I did not know whey were this easy to rebuild. Unfortunately these particular ones are sealed on the ends molded plastic caps for the lead wires. There are 5 relays in the 501A that handle the high voltage ranges. I am having issues with 60, 20 and 6. With them also causing some havoc on auto range as well. When I have a situation where they are working the unit locks in and works as expected. These are supposed to have a 5Vdc coil but when I was testing one with a square wave it would not trip till about 8Vdc. In the 501A all the relays are energized by the output of a hex inverter then they are allowed to fall low and open. These are energized = Closed I believe. The odd thing about these is they are DP ST relays as they cover + and - inputs with the same relay. These are silver packages with 4 legs on one side and 2 on the other. 2 outer legs are for the coil the 2 inner ones are for the reeds running straight through. This 501A is worth saving especially this one as it has option one the intermodulation measurements. Of course it will need a full cal after words. Being double pole has caused me a fair bit of grief in the replacement department. Eric -----Original Message----- From: [email protected] < [email protected]> On Behalf Of Dennis Tillman W7pF Sent: Sunday, April 4, 2021 12:57 PM To: [email protected]Subject: Re: [TekScopes] Reed relays for a sick AA501A Hi Eric, Reed relays are conceptually simple devices in electrical and in mechanical terms. There are only two parts - the reed- and a coil wrapped around it. The reeds come in two types: the more common ones have normally open contacts. The less common ones have normally closed contacts. The coils are designed to operate on a specific voltage like +12VDC, +15VDC, or +28VDC. Coil resistance is dependent on the operating voltage. I have a bunch of the glass reeds I picked up somewhere 50 years ago and every few years I find a use for one of them. The reeds themselves are cheap and probably available on eBay for a few dollars for a handful of them. The only thing that matters is the diameter of the glass envelope surrounding the reed and the length from one end to the other of the contact pins. It is good to have an assortment of sizes to work with. A bad reed can almost always be slid out of the coil and replaced with one that is approximately the same size. You can't bend the leads (even slightly) or that will break the glass. But you can cut them down to size. You can hear the reed make and break contact (if you are in a quiet room) to determine the reed closes BEFORE the proper voltage is applied to the coil. For instance, a 12V reed relay should close when you apply about 8V to it. Dennis Tillman W7pF -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Eric Sent: Saturday, April 03, 2021 8:25 PM To: [email protected]Subject: [TekScopes] Reed relays for a sick AA501A I have a sick AA501A that I am trying to bring back from the dead. I am wondering if anyone knows of any replacement reed relays. The existing part is Tek number 148-0134-00. The part number on the part is EAC 2A05X250biaa. If there is not a supply of these or if these are troublesome parts I am looking at a possible modern replacement. Coto 2332 Mouser part 816-2332-05-010 . It will need some adaptation of course but it does look like it will fit physically. Eric -- Dennis Tillman W7pF TekScopes Moderator -- Dennis Tillman W7pF TekScopes Moderator
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Re: 492P signal amplitude error and error 58
Thank you very much, I try.
--Cheers
Attilio
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Re: 492P signal amplitude error and error 58
Having experienced the same problem with a 494P I read somecomments about this on KO4BB -site.
I ended up replacing U1050 (74LS74) and U2050 (74LS10)on the A50A3 offset mixer board. I hesitated at first but usedlow profile high quality DIP sockets and the analyzerworked OK after this.
All the best.
Ulf KylenfallSM6GXV
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Re: Tek 2430 Works Fine for 15mins Then Freezes
Thanks, Mark.
Yes, the RIFA caps are there. Two of them. They'll get replaced.
Your heating theory of the cold solder joint is very plausible. I'll start replacing the electrolytics and see what happens.
Now its a matter of getting the low voltage board out or its bottom at least exposed.
BTW, how do I attach a jpg to a message?
John
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7L12 spur at 210MHZ - Request for test results or suggestions?
For 7L12ers: Can you run a quick test, please?
I have been restoring a 7L12 for a while now. First was the Weinschel input attenuator, toasted by excessive input. A long rebuild using parts cannibalized from a similar but physically incompatible Weinschel unit. Next was a loss of 20dB through the 30KHz bandpass filter which responded to vibration around the prefilters (possibly cracked solderwork - gone for now),
The unit now passes all performance tests except one, the test for spurs (Item 7, Page 3-4 of the manual). There is only one spur above the -100dB noise floor, -80 to -85dB at 210MHz (2nd harmonic of the105MHz IF). It does not respond to changes in the input attenuator setting but does respond accurately to changes in the Gain Selector or Variable Gain controls. Switching in the 300Hz video filter drops the noise floor to about -106db and suppresses the spur to about 2db above this (-104db). The other video filters and the video processor have no effect. It's not an image (tunes in the correct direction), and it seems not to be a harmonic (tunes at the normal rate). Note that the dB figures refer to the 1st mixer input and are 30db lower than the displayed Reference Level (per the Tek manual).
Could anyone with a 7L12 and ideally in a 7854 run this test from Page 3-4 and look for a spur at 210MHz (or at other frequencies as well) and post the results? My 7L12 is stock, SN B192xxx, with the LED Reference Level readout and LO output jacks.
The setup is: No input cables, RF attenuator at 30db, gain selector fully CCW, and variable gain in CAL detent. The Reference Level should show 0dbm on screen and in the LEDs. Set the Span/Div to 1MHz, the Resolution Bandwidth to 30KHz, and the Time/Div to Spectrum and Cal. In 2db/Div, set the baseline to the bottom graticule line. Switch to 10db/Div and tune to around 210MHz, looking for a spur. Also, do a manual tuning scan from 0 to 1800MHz looking for other spurs.
Results and comments gratefully received.
Cliff
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Raymond Domp Frank
Dave Peterson
David C. Partridge
Attilio