Recently there was a discussion about what replacements are available for replacing the pass transistors in TM-5xx power supplies, but I can't find it, nor can I remember in which Yahoo group the discussion occurred. Can someone point me to that thread?
Thanks.
DaveD
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Check to make sure that the fuse that blew is the correct type of fuse.
I have a 7934 that arrive with a similar problem. When I finally thought
to check the fuse type, I found that it was incorrect. Installing the
correct fuse fixed the problem.
DaveD
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On 9/27/2014 11:31 AM, thierry.delaitre@... [TekScopes] wrote:
Hello
I have a 7704A which had been stored for quite a while¡
it worked ok for 10mn and then one of the two fuse went off.
i'm not sure whether it is the fuse for the line circuit or inverter.
The schematic for the 7704A seems hard to find. Would anyone know
where i can find it or kindly send the relevant part for the switched
mode power supply? I'm new on the 7704A !
Kind Regards
Thierry.
[Non-text portions of this message have been removed]
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thanks John/Jerry
Yep found the schematics at
I only checked the A4 file earlier. the schematic is actually in the A3 file.
It is the 4 amp fuse which has blown up. The 2A fuse is ok so most likely to be the bridge rectifier and/or the 550uF caps. Will check.
Thanks
Thierry.
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Re: Shares in 453's rising.........
Good grief, there should be a law against spelling it "Tektronics". It's right there on the front panel! How hard can it be to spell?
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Hi,
You can start by testing the bridge rectifier for a shorted leg. The electrolytic capacitors are always suspect but you usually have click mode on those. Google Tektronix 7704a manual for a list of sources. You should be able to get a free one.
Jerry Massengale
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-----Original Message-----
From: thierry.delaitre@... [TekScopes] <TekScopes@...>
To: TekScopes <TekScopes@...>
Sent: Sat, Sep 27, 2014 12:31 pm
Subject: [TekScopes] 7704A fuse has blown
Hello
I have a 7704A which had been stored for quite a while¡
it worked ok for 10mn and then one of the two fuse went off.
i'm not sure whether it is the fuse for the line circuit or inverter.
The schematic for the 7704A seems hard to find. Would anyone know where i can find it or kindly send the relevant part for the switched mode power supply? I'm new on the 7704A !
Kind Regards
Thierry.
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
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Thierry,
Try ko4bb.com.
--John Gord
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Hello
I have a 7704A which had been stored for quite a while¡
it worked ok for 10mn and then one of the two fuse went off.
i'm not sure whether it is the fuse for the line circuit or inverter.
The schematic for the 7704A seems hard to find. Would anyone know where i can find it or kindly send the relevant part for the switched mode power supply? I'm new on the 7704A !
Kind Regards
Thierry.
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Re: Tek 310 HV transformer
Hello Manfred,
I am aware that your thread has drifted away from the original topic. So, I just wanted to let you know how much I have enjoyed reading over your hydro-energy "adventure"
And you have my true respect for your courage and skilled craftmanship. I do not know anybody else who decides to design and build an Electronic Load Controller or a 10 kVA transformer/substation. Well done!
Cheers,
Magnus
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Re: Shares in 453's rising.........
On Sat, 27 Sep 2014 11:06:50 -0500, you wrote: On 09/27/2014 08:54 AM, David davidwhess@... [TekScopes] wrote:
I was not being serious. :)
To me it is just a TM500 universal counter which happens to have an interesting
sticker on it
I'm sure some of us have gear used to make history, and some of it
could even be valued for its appearance in parts on the wall
instead of going to the scrap yards.
Gold price sure is killing off 70's gear with thick plating...
I left on the neat tidy ID tags of my plugins and modules from Sandia,
Fermi Labs, Sprague, IBM... I have various 7000 plug-ins marked GM, NAVY, and USAF but I think the DC505 marked NASA GRC is the most interesting to see. I have a directional power meter from the USS Kansas City Wichita-class replenishment oiler. My favorite is a 7B92A timebase prominently marked Applied Physics in red marker which came with a broken sweep (since repaired) that made time go backwards. I refer to it as my Dr. Who timebase. I have a couple of 5.25" hard drives with the covers removed being used as book ends. The first thing I think of when reading "some of it could even be valued for its appearance in parts on the wall" is the Minuteman guidance computer Jim Wililams had:
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Re: Shares in 453's rising.........
On 09/27/2014 08:54 AM, David davidwhess@... [TekScopes] wrote: I was not being serious. :)
To me it is just a TM500 universal counter which happens to have an interesting
sticker on it I'm sure some of us have gear used to make history, and some of it could even be valued for its appearance in parts on the wall instead of going to the scrap yards. Gold price sure is killing off 70's gear with thick plating... I left on the neat tidy ID tags of my plugins and modules from Sandia, Fermi Labs, Sprague, IBM...
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Sounds like a PSU job.
Tektronix 2465 300Mhz 4 Channel Oscilloscope (Parts or Fix)
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Re: Shares in 453's rising.........
On Sat, 27 Sep 2014 08:00:35 -0500, you wrote: On 09/26/2014 05:13 PM, David davidwhess@... [TekScopes] wrote:
I have a Tektronix DC505 which came from NASA's Glenn Research Center. What do
you think it is worth?
It's not a very framable example of electronics as art, or it might sell.
I sold 5 old "probably ex NASA" circuit boards to someone in Hong Kong.
They came from a sealed bid surplus sale by the old GSA that my dad
bought at the old Ellington air force base -- Houston, near NASA...
They were framable examples though. I was not being serious. :) To me it is just a TM500 universal counter which happens to have an interesting sticker on it and a couple of new problems that need fixing. Unusually for a direct reading universal counter and like a 7D15, it operates up to 225 MHz. Most top out at about half that.
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Re: Shares in 453's rising.........
On 09/26/2014 05:13 PM, David davidwhess@... [TekScopes] wrote: I have a Tektronix DC505 which came from NASA's Glenn Research Center. What do
you think it is worth?
It's not a very framable example of electronics as art, or it might sell. I sold 5 old "probably ex NASA" circuit boards to someone in Hong Kong. They came from a sealed bid surplus sale by the old GSA that my dad bought at the old Ellington air force base -- Houston, near NASA... They were framable examples though.
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Re: Tek 310 HV transformer
That's good news.
When you say "Z" do you mean you wound one multi turn layer and then came
strait back to the starting side?
Or did you take a turn or two to come back to the starting side?
If so did you insulate below and on top of the way back?
Did you reuse the core?
Any picts would be most interesting before it gets "canned"
Please start a new thread asking about the 453 winding spec, I think that
will help people search in the future
John
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-----Original Message----- From: TekScopes@... [mailto:TekScopes@...] Sent: Friday, September 26, 2014 4:21 PM To: TekScopes@... Subject: RE: [TekScopes] Re: Tek 310 HV transformer My HP 740B rewind is 18 hours and counting, at full power. It runs cooler than the original! We switch at 20kHz, putting out about 30W at 1000VDC. It's 40t of #18 Temco GPMR-200, Faraday shield, then 1600t of #32 in nine Z-wound layers. I insulated it with clear acrylic packing tape. One layer of tape between wire layers, and, because it has to take 500V, three layers on the shield. In a few days I'll put it in a can, mount it up, and keep going. If it holds, I will have enough confidence to try a rewind on my 453, if removing the original's outer epoxy isn't enough. Does anybody have the 453 transformer winding spec? I didn't see anything searching on Yahoo. Dave Wise ________________________________________ From: TekScopes@... [TekScopes@...] Sent: Wednesday, September 24, 2014 11:53 AM To: TekScopes@... Subject: Re: [TekScopes] Re: Tek 310 HV transformer Hi Manfred, Manfred Mornhinweg manfred@... [TekScopes] wrote: You have created an interesting experiment. Please keep
an eye on it and report back in a year or so.
------------------------------------ Posted by: David Wise <David_Wise@...> ------------------------------------ ------------------------------------ Yahoo Groups Links
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Re: Tek 310 HV transformer
My HP 740B rewind is 18 hours and counting, at full power. It runs cooler than the original! We switch at 20kHz, putting out about 30W at 1000VDC. It's 40t of #18 Temco GPMR-200, Faraday shield, then 1600t of #32 in nine Z-wound layers. I insulated it with clear acrylic packing tape. One layer of tape between wire layers, and, because it has to take 500V, three layers on the shield. In a few days I'll put it in a can, mount it up, and keep going. If it holds, I will have enough confidence to try a rewind on my 453, if removing the original's outer epoxy isn't enough. Does anybody have the 453 transformer winding spec? I didn't see anything searching on Yahoo. Dave Wise ________________________________________ From: TekScopes@... [TekScopes@...] Sent: Wednesday, September 24, 2014 11:53 AM To: TekScopes@... Subject: Re: [TekScopes] Re: Tek 310 HV transformer Hi Manfred, Manfred Mornhinweg manfred@... [TekScopes] wrote: You have created an interesting experiment. Please keep
an eye on it and report back in a year or so.
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Re: Shares in 453's rising.........
David,
I used to have a model railroad repair and sales store. I would go
find stuff at hobby shops all around the country and bring it home. Then
we would clean it up, inspect and repair as necessary, and list it on
E-bay. Yes, I was selling most of the stuff at what it sold for back in
the seventies but it was all in top notch condition and it was selling
for a fraction of what the same items would cost today. Cars were
running from 2-10 and locos were from 10-50. Track was running from a
few cents to a couple of dollars.
Thanks,
rich!
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On 9/26/2014 5:17 PM, David davidwhess@... [TekScopes] wrote:
I have occasionally run across others who do the same thing. I assume
they find
the old prices in a catalog and then apply a discount. Maybe they
account for
inflation as well to bring the value up to the true price.
Listing anything which might make the item more desirable like origin
is just
good marketing.
On Fri, 26 Sep 2014 17:08:43 -0500, you wrote:
Hello all,
Out of curiosity I took a look at everything on this person's site.
Wow! He must believe that this stuff is going to be bought by hard up
collectors. The prices are almost retail for the items when they were
brand new. Hum!
Thanks,
rich!
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Re: Shares in 453's rising.........
I have occasionally run across others who do the same thing. I assume they find
the old prices in a catalog and then apply a discount. Maybe they account for
inflation as well to bring the value up to the true price.
Listing anything which might make the item more desirable like origin is just
good marketing.
toggle quoted message
Show quoted text
On Fri, 26 Sep 2014 17:08:43 -0500, you wrote: Hello all,
Out of curiosity I took a look at everything on this person's site.
Wow! He must believe that this stuff is going to be bought by hard up
collectors. The prices are almost retail for the items when they were
brand new. Hum!
Thanks,
rich!
|
Re: Shares in 453's rising.........
I have a Tektronix DC505 which came from NASA's Glenn Research Center. What do
you think it is worth?
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On Fri, 26 Sep 2014 12:29:22 -0700, you wrote: Well you need the voltmeter to go with it: 161416507578 and to get power to
your project you might also need this cable 151405093904. I think that sums
it up
John
I'm a 453 devotee, but never-the-less, intrigued by the asking price here:
ebay item 161416507593 ??
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Re: Shares in 453's rising.........
Hello all,
Out of curiosity I took a look at everything on this person's site.
Wow! He must believe that this stuff is going to be bought by hard up
collectors. The prices are almost retail for the items when they were
brand new. Hum!
Thanks,
rich!
toggle quoted message
Show quoted text
On 9/26/2014 3:04 PM, Druid Noibn druid_noibn@... [TekScopes] wrote:
Hi,
I looked over the offerings - wow. If the seller gets those prices,
I'm quitting my day job. I love the price on the conduit coupler.
What a waste of bandwidth.
Be well,
DBN
On Friday, September 26, 2014 3:29 PM, "'John Snyder'
Kochcal@... [TekScopes]" <TekScopes@...> wrote:
Well you need the voltmeter to go with it: 161416507578 and to get
power to
your project you might also need this cable 151405093904. I think that
sums
it up
John
I'm a 453 devotee, but never-the-less, intrigued by the asking price here:
ebay item 161416507593 ??
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Re: Shares in 453's rising.........
Hi,
I looked over the offerings - wow. If the seller gets those prices, I'm quitting my day job. I love the price on the conduit coupler.
What a waste of bandwidth.
Be well,
DBN
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Show quoted text
On Friday, September 26, 2014 3:29 PM, "'John Snyder' Kochcal@... [TekScopes]" <TekScopes@...> wrote:
Well you need the voltmeter to go with it: 161416507578 and to get power to
your project you might also need this cable 151405093904. I think that sums
it up
John
I'm a 453 devotee, but never-the-less, intrigued by the asking price here:
ebay item 161416507593 ??
[Non-text portions of this message have been removed]
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David Hess