Tektronix 475 sweep triger repair??

kg...@msbx.net

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May 17, 2011, 9:25:48 AM5/17/11

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I have a older TEKTRONIX 475 Oscilloscope that needs repair, the sweep will not trigger either
channel 1 or 2, it auto sweeps fine. I have checked & re-plugged all connections possible with no
improvement.. Might anyone have any suggestions as to a potential. reasonable, cheep, repair,
recalibrating person in the central Michigan area? I have checked with Tektronix repair locations
in the north east USA but there minim prices are in the high hundreds just to check it out.

*********************************
Thank you. k...@msbx.net

abrsvc

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May 17, 2011, 10:43:16 AM5/17/11

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If you have repair experience yourself, you may want to search for the
service manual for the 475. I was able to locate on for my 2445B
scope. I have seen tehse on Ebay and Craigslist.

Dan

PeterD

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May 17, 2011, 12:56:26 PM5/17/11

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On 5/17/2011 10:43 AM, abrsvc wrote:
> On May 17, 9:25 am, k...@msbx.net wrote:
>> I have a older TEKTRONIX 475 Oscilloscope that needs repair, the sweep will not trigger either

>> channel 1 or 2, it auto sweeps fine. I have checked& re-plugged all connections possible with no

>> improvement.. Might anyone have any suggestions as to a potential. reasonable, cheep, repair,
>> recalibrating person in the central Michigan area? I have checked with Tektronix repair locations
>> in the north east USA but there minim prices are in the high hundreds just to check it out.
>>
>> *********************************
>> Thank you. k...@msbx.net
>
> If you have repair experience yourself, you may want to search for the
> service manual for the 475. I was able to locate on for my 2445B
> scope. I have seen tehse on Ebay and Craigslist.
>
> Dan

Also a post on the Yahoo Tek group would be very, very valuable.

--
I'm never going to grow up.

mike

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May 17, 2011, 2:16:02 PM5/17/11

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http://www2.tek.com/cmswpt/madetails.lotr?ct=MA&cs=msv&ci=15845&lc=EN

Start troubleshooting in the vicinity of the tunnel diodes on schematic 6.

Jim Yanik

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May 17, 2011, 5:31:09 PM5/17/11

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PeterD <pet...@hipson.net> wrote in news:iqu9br$21rd$1...@pyrite.mv.net:

next question would be;does it externally trigger?
It could be a blown trigger input FET(matched pair),a bad trigger amp
IC(155-0032-xx)
You could swap parts from B trigger.Use anti-static protection.

Hopefully,it's not a Peltola center pin foldover.
(mini coax cable center conductor folded over when reinserting the
connector into the socket,a common occurrence,and an easy mistake to make.)

Does auto sweep trigger or only free run?

--
Jim Yanik
jyanik
at
localnet
dot com

JW

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May 18, 2011, 5:40:34 AM5/18/11

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On Tue, 17 May 2011 09:25:48 -0400 kg...@msbx.net wrote in Message id:
<i6s4t6dej0p2v84nm...@4ax.com>:

You'll find lots of folks who may be able to help you here:
http://tech.groups.yahoo.com/group/TekScopes/

KG

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May 18, 2011, 8:58:40 AM5/18/11

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Thank you all for your assistance. I have just joined the Yahoo tektronix group and awaiting
approvial. I'm unsure of the external triger, I will retest to be sure.
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Thank You kg...@msbx.net

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