Date   

Re: Members in Australia

romeo987
 

John,
Tek (and other “vintage” stuff) fan here in Adelaide. Would be interested to know what you have.
Roman


Re: Members in Australia

Simon Owen
 

Sydney, 2131. And helplessly addicted.

On Tue, 6 Jul 2021, 12:51 pm penguin2004au, <clansman2011@gmail.com> wrote:

Greetings all:
Just curious to see how many members are Down Under,
if only because I might
have to downsize my collection soon.
Regards: John.






Re: 7603 P.S. cans, slow warm-up and focus control

emissionlabs
 

This is just from the days when I did TV repair. I don't know if it applies to TEK CRT.

Provided all voltages CRT are good (including heater voltage) perhaps the cathode has reduced emission. Initially that gives little problems. There are ways to find this out quickly, leaving everything in place.


Re: Members in Australia

David Hopkins
 

I'm also here in Australia.
Up in Queensland.

David

On 2021-07-07 2:58 pm, VK1GVC wrote:
John et al, I'm in Aus, in Canberra.

And what's with this Melbourne/Vic thing?  All geographically identifiable replies below seem to be from your part of the world!

Regards,

Graham

On 6/07/2021 12:51 pm, penguin2004au wrote:
Greetings all:
                      Just curious to see how many members are Down Under, if only because I might
                 have to downsize my collection soon.
Regards: John.







--
Definitely not sent from an I-Phone

David G Hopkins (VK4ZF)


Re: FTAGH: Free to a good home: 465/475 scopes

Gordon Smith
 

Hi Jeff,
I must most strongly advise you to NOT ship this scope (or any other item that can be broken) via UPS. Having them pack it is fine, but please do not ship via UPS. I and many others have had nothing but bad experiences with them for breakable items. As was recommended to me once, if you are shipping something with UPS please pack assuming that your item will be dropped 12 ft onto a hard concrete floor. And I am not joking. If you really want the scope to make it through the mail, please please ship via Fedex or USPS. That is just my experience, YMMV.

73, Gordon KJ6IKT

On Tue, Jul 6, 2021 at 03:36 PM, Jeff Davis wrote:
Sure, I can do that, no problem. If it makes no difference to you, the UPS
store is somewhat more convenient for me.

Jeff
On Jul 6, 2021, at 3:29 PM, greenboxmaven via groups.io
<ka2ivy=verizon.net@groups.io> wrote:

Would you be willing to take one or two of the scopes to a Fedex store,
they can pack and ship them with no further effort on your part and I can do
all of the payment from my end. Thanks,

Bruce Gentry, KA2IVY


Re: Members in Australia

VK1GVC
 

John et al, I'm in Aus, in Canberra.

And what's with this Melbourne/Vic thing?  All geographically identifiable replies below seem to be from your part of the world!

Regards,

Graham

On 6/07/2021 12:51 pm, penguin2004au wrote:
Greetings all:
Just curious to see how many members are Down Under, if only because I might
have to downsize my collection soon.
Regards: John.




Semi-OT: protoboards as seen in (aftermarket) 7K plugin 'Automatic 9-16 Point Rasterizer'

Christian
 

https://w140.com/tekwiki/wiki/Automatic_9-16_Point_Rasterizer

I like the look of those protoboards/connectors/card guides. Does anyone recognize make & model? Double bonus points for a source.


Re: Members in Australia

momemeca
 

Another Tek collector / restorer here in Oz (Mornington Peninsula).
Would love to hear from you :-)
Cheers,
Rick.


Re: FTAGH: Free to a good home: 465/475 scopes

Rey
 

Hi Jeff,
I would love to get 2-3 (475/475A), I'm in San Diego so I can drive up there best during the week if possible. cis181ellin@yahoo.com
Thanks


Re: Members in Australia

Steph L
 

Hi John,

I'm also in Melbourne (3156) and long time Tek gear fan.

Great to hear from you and other locals. :)

Kind Regards

Steph


Re: FTAGH: Free to a good home: 465/475 scopes

David Baum
 

Hi Jeff,

I'd be interested in picking a unit or two (or three?).
Can you contact me at davidbaumtek@gmail.com for more details?

David


Re: Members in Australia

David Turner
 

Hello,
I'm also in Melbourne.
Thanks,David


Re: Members in Australia

Morris Odell
 

Hi John,

I'm in Melbourne. Let me know what you have available.

Cheers,

Morris


Re: Members in Australia

tinkera123
 

Yep, Aussie member here. PM sent to you also.
--
Cheers,
Ian,
Melbourne, Australia


Re: My 475

Rey
 

Hi Dave,
Thanks for the advice, check the F1318 and is fine. So now I'll order a couple of tools and some caps, as soon as they are in I'll continue. Mean while I'll re read the troubleshooting guide from tektronix also read more on 475. As far as visible goes nothing looks or smells bad. The story will continue, as a side note I finally paid attention to the tag in the back of the scope. Came from the navy, "fleet numerical weather central" go navy.

rey


Re: 7603 P.S. cans, slow warm-up and focus control

 

On Tue, Jul 6, 2021 at 11:59 PM, Mark Vincent wrote:


The scope has always been slow to show a trace.
Hi Mark,
Apart from the usual checks, you may consider checking the HV inverter. More specifically, you may want to have a look at the feedback loop. A more conductive Q1214 results in a harder base drive of Q1216 and Q1218, increasing HV.
You could have a leaking C1240 (15uF), below the x4 HV multiplier in the schematics.
The right side of R1201 (10kOhm), below T1225 in the schematics, is a safe place to look at the regulation.
The voltage at the anode of CR1244 (50.6V) is the (positive) reference for the HV stabilization. Pin 6 of R1245 pulls down and pin 3 carries the "comparator" voltage; the ratio of R1245A and R1245B determines the voltage at stability. The higher the voltage at R1245 pin 3, the higher the HV will (or should) be.

Raymond


Re: FTAGH: Free to a good home: 465/475 scopes

Jeff Davis
 

Sure, I can do that, no problem. If it makes no difference to you, the UPS store is somewhat more convenient for me.

Jeff

On Jul 6, 2021, at 3:29 PM, greenboxmaven via groups.io <ka2ivy=verizon.net@groups.io> wrote:

Would you be willing to take one or two of the scopes to a Fedex store, they can pack and ship them with no further effort on your part and I can do all of the payment from my end. Thanks,

Bruce Gentry, KA2IVY





On 7/6/21 16:53, Jeff Davis wrote:
Hi All,

I have roughly 25 Tek 465, 465B, 475, and 475A scopes, some with DMMs, available free for local pickup in the Orange County, California area.

These are in various stages of functionality from fully functional to won't turn on. Most have had some preliminary troubleshooting but I haven't attempted to repair any of these.

My intention was to fix them up and resell them on eBay as a retirement project. I found that the market prices for them didn't justify the time and effort to refurbish them (for someone else. For my own use is a different story!).

Unfortunately, any of these that aren't gone in a month or so will end up in the landfill, so I'd really like to see them find good homes. That said, I don't want to ship them - local pickup only.

73,

Jeff / N0DY







Re: FTAGH: Free to a good home: 465/475 scopes

greenboxmaven
 

Would you be willing to take one or two of the scopes to a Fedex store, they can pack and ship them with no further effort on your part and I can do all of the payment from my end. Thanks,

Bruce Gentry, KA2IVY

On 7/6/21 16:53, Jeff Davis wrote:
Hi All,

I have roughly 25 Tek 465, 465B, 475, and 475A scopes, some with DMMs, available free for local pickup in the Orange County, California area.

These are in various stages of functionality from fully functional to won't turn on. Most have had some preliminary troubleshooting but I haven't attempted to repair any of these.

My intention was to fix them up and resell them on eBay as a retirement project. I found that the market prices for them didn't justify the time and effort to refurbish them (for someone else. For my own use is a different story!).

Unfortunately, any of these that aren't gone in a month or so will end up in the landfill, so I'd really like to see them find good homes. That said, I don't want to ship them - local pickup only.

73,

Jeff / N0DY




7603 P.S. cans, slow warm-up and focus control

Mark Vincent
 

I have a 7603 I ordered new electrolytics today and will install them on
Fri. when they come in. The scope has always been slow to show a trace. The
crt is good. I tested it. It tested good after about 10-15 seconds as a
good tube would. The rest of the scope has been overhauled with new filters
and resistors as needed. Since the main filters are original, is the age of
these causing the slow warm-up, about 45 seconds? When it is warmed up, the
trace looks great. At this time, there is a slight intensity modulation on
the trace which I suspect are the filter cans going bad. I have heard that
at least one electrolytic in the supply is known to go bad first with the
others soon to follow. I have seen a picture of a 465 with bad caps with
the weird trace, not a 7603, yet. Mine still has a line as it should. I
ordered ones that are high temp, low ESRand long life. I know about the
ground lugs needing bridging. I do not know if the 76x3 series takes longer
to warm-up or not. The B+ voltages are right. I did set the fan voltage to
the high position which keeps it cooler than at the low position.

I am looking for a small pot to replace the focus pot in this scope. The
original is 50,000 ohms 1/2W. Mine burned up. There is 150V across that
pot. A 2W should have been used. I put in a smaller value pot with
resistors on each end. The shaft would be adjusted with the right side off.
I did keep the original to swap shafts so adjustment can be done from the
front if needed. A smaller value, e.g. 20,000 ohms, would be fine as I will
put resistors on each side of the pot to keep the centre position of the
pot at focus. It is the small diameter shaft, not the standard size.

Mark


Re: My 475

 

On Tue, Jul 6, 2021 at 10:53 PM, Rey wrote:


I was checking all the voltages and the only thats off, is the the 50v unreg
which reads 69,6 V
That's fine, it's just the unregulated voltage, straight from transformer secondary, rectifiers and buffer caps that the regulated 50V is derived from in the 'scope.

Raymond

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