Thanks a lot, Håkan. Will try that during the coming week and share result. Raymond

hello to all, i can´t find the part 2n5859 here in Mexico, this part number is critical in the -15v regulator performance or permits substitution ? any possible subtitutes? any help will be

Hello, first post here and first real scope. A tech friend of mine gave me this in broken condition and said I could keep it if I can fix it. So here goes.... It doesn’t boot. Nothing happens

When I move channels 1 or 2 down the screen the trace is compressed at the bottom. As if the gain near the bottom the screen is about half that at the top. The effect is identical on both channels.

Dear TekScopes Could someone a bit more competent than me help with analysing the problem I am having with the Z-Axis Amp on my beloved 475 which has served me incredibly well for over 10 years. The

Don't condemn the vertical hybrid just yet. First, check that you have all of the proper power supply voltages at U119 on the motherboard (see manual). Next, check for a bad connection to the pins

Chuck, thanks for the advice. I swapped U400 with one from a 2465 and that fixed the problem. One day I may try to fix the 2465 but it has a stubborn intermittent that I've never managed to fix. So I

For decades I have looked at mains noise and distortion with a Beckman CT232 AC current clamp. It has a bandwidth of 30 Hz - 10 kHz and a range of 1-1000A. Its output is in ma per volt. I use it to

Tek TDS 3014 scope Boots up & passes all 8 self-tests , but reports a "System Error" in the Graphics System: ( The BootUp Self-Test passes everything, including 'Application modules' -- even

There is a DALLAS DS1742W-150 Timekeeping RAM that might or might not be the problem. Some time ago I had a TDS 3014B that got stuck on the flash screen. Fortunately I had a scrapped main board from

Did you check the mains fuse and switch? Raymond

Fuse: yes. Switch: no, and I should have because that’s an easy one and have had bad switches on other gear Thanks, Raymond, I will check the switch tonight after work Nick wrote:

Is it in a TO-39 (metal) case? Try findchips.com. Several sources to choose from, though Mouser is out of stock.

Yes it is TO-39, thank you Best regards. Pio

Just wanted to ask your advice, On the local auction someone put 2445a (exactly the same like mine) for the bargain price - 100 USD delivered. I wonder whether this is worth buying. Apart from a

After seeing a tip here on a 2465 for sale for $50 plus shipping, I bought it.  It was advertised as having a bad horizontal switch - it had been dropped on it.  Well they were right, it was bad. 

Thank you John, For me also it's difficult to walk by this advertised 2445a, especially, since it seems like it has nothing broken at all... And for many things including the phase measurements the

I have a 2247A myself, excellent GP scope. One of the first recommended things to do I was told is replace all the rectifier diodes in the A18 LV power supply that have ZM or ZS markings on them as

I have two 475 scopes. Both have developed a similar probe calibration problem on one channel. I am using the scope calibration signal. I have verified results with multiple probes First scope -

Thank you, Alex. This must have been the suggestion I saw here not too long ago, I just got the impression that the diode list was an abridged tally of what “should” be checked and replaced.