Hi Phillip. I see you are getting some very good help on this problem, and when you combine that with the fact that your voltages are only down by half, I'd say the 2225 is only lightly wounded and th

I have had zero involvements with anyone involved in your story... except reading your unfortunate rants about it. tom jobe... [Non-text portions of this message have been removed]

The whole world can see the bid history of every eBay auction everyday. The auction, the bidding process and bidding history you are raving about was absolutely ordinary with no hint of foul play. The

it seems to me that you need to study up on how the eBay bidding process works. From looking at the bid history, I'd say the auction was all quite normal, and someone simply bought it for one bid incr

In this thread the 151-0140-00 transistor was mentioned as also being used in scopes like the 7603, and I had the same experience Fabio had where nothing except a homotaxial RCA 2N3055 would work as a

In a recent 2235 repair discussion a 22xx update modification document that came from Tektronix as part number 050-2242-03 was mentioned. It is available on Hakan's web site at: http://hakanh.com/dl/d

Thanks Ed, That's an angle I never thought of... when the power switch is still turned on and then the electrical cord gets pulled from the wall... Ouch! Whatever there is to bleed off the charge, it

Thank you Harvey and Ed for your informative replies! I failed to mention that this C904 capacitor is immediately after the power switch and immediately before the input to the full wave bridge, so th

Could anyone offer an opinion on this question? In re-capping the power supply in a 2215A I've been working on, I ran into a little dilemma about the capacitance value of C904. C904 is a line to line

The other X and Y capacitors you might consider replacing are C904 (just behind the power switch on the mainboard and under the IEC module) and C900 on the A6 filter board. C904 is 'line to line' but

Hi Mike, Thank you for the report on your successful repair! Replacing the larger electrolytic capacitors (10uF and up?) does a lot of good for a 22XX scope in many subtle ways. I believe you are in a

Thank you Chuck... for the capacitor lesson. That's a fine document you put together! As others have pointed out, we get to learn all sorts of good things on Tekscopes. tom jobe... [Non-text portions

Just for the record, a better testing method on a repaired 2215A shows that U930 is running Q9070 at about 71 kHz (a period of around 14 uS). I used pin 7 as the ground and pin 10 (going to Q9070) as

Yesterday I said that U930 operated in the 20k to 24k range, and that was wrong. The inverter/primary side of the main transformer T948 runs at something like that, but U930 has its own frequency to r

Thanks Ed for that message number from 2012! That leads us to some other comments in the same thread. I have not run into this problem on any 22xx's, but I'm sure it is just because my hearing is gone

Wouldn't it be good to try changing C907 as the document suggests? It is directly connected to T906 and it was given as a possible problem in Hakan's document, plus you have already had CR907 looking

Thank you Hakan! This kind of good information is very rare to see, and hopefully it will help the current 2235 problem being worked on. This information will help many folks in the future! tom jobe..

Look at each link, it is the actual link repeated more than once. Just select from the start of the link to the first space, or edit the duplicates out when the whole link Leo posted is in your search

Hi Walter, I have a 2252 service manual that I bought from Qservice in Greece years ago, so I can't send you a copy of it. It appears to be very complete. See if Qservice still sells it. tom jobe... [

Hi Kevin, It's good to see you are still monitoring the Tekscopes group, and helping where you can! That was a heroic repair you did on your 2235 power supply! I don't remember the details, but I know