The lack of an MCP is why I went with the 7904 as apposed to the 7104. Due to the difficulty of being able to source a tube if I needed one.

What is the DTM mechanical max CCW reading ? It should be 0.20 http://www.hakanh.com/dl/docs/hardtofind/dtmsettings.pdf /Håkan

That's correct or you wouldn't experience the writing rate being as "limited" as with all the other regular models. Raymond

Just wanted to chime in and let people know that they're also available at a slightly lower cost on www.n0dy.com<http://www.n0dy.com>. The cost there is lower because Ebay doesn't take a cut as a

AFAIK, the 7904A does *not* use and MCP CRT. The 7104 and 2467 do use MCP CRTs. DaveD

Hi guys, I need your help again, I am trying to do horizontal calibration on my 465 but I cannot set step one of calibration, "Check/Adjust Sweep Start and A Sweep Calibration", With Sweep start

The two most common faults causing the P/S to go into burst mode I've seen on the 224x supplies have been one or more shorted rectifier diodes on the secondary or a bad HV multiplier. Another not so

Looks like my frame needs a bit of a tune up then. Ill be working on this once I get the current plugin done. I have shied away from the MCP CRT as read some where that those tubes were all on

A lot of potential problems seem to have been eliminated. Next I would start looking for a potential overload on the power supply which may (or may not) cause the PS to go into a shutdown to protect

I understand. And you’re absolute right. I did with what I had available at the time. Best Regards, And thank you for your time and effort. Sent from my iPhone 7 Stephen S.

It's a much-talked-about complaint. In this particular case, it's unlikely since the transistors in question only operate in unusual cases - power off and overload, respectively. But since we're

Thanks Brian.  Searching online for information on the Velleman boards, I see that Jameco https://www.jameco.com/z/EDU06-Velleman-Oscilloscope-Tutor-Kit_2175568.html offers them for $29.99 . 

Ooh ok. Now I understand. You were talking about oscillation. This is the thing I didn’t grasp before from your previous post. Thank you for clearing that out. Do you think that could bean

To replace 2N3565 in the SC502 power supply, BC639 is better than 2N2222A, 100MHz vs 300MHz. Under a dollar at Mouser. But the best choice is KSC1008. It's only 30MHz - perfect to avoid oscillation

Hi Roger, I have the IC based Y amplifier. I will proceed today with your instructions. Thanks a lot! Luis

My father has ARMD (81yo), so I should be careful too. I concur!

I think that is a problem fundamentally every proofreader has. Confirmation bias in the small. (Earlier in my life, I experienced the eyesight of my father deteriorate over a span of a decade.

Well, the key to good proofreading is to be able to see the mistakes. And since my retina was damaged by my vitreous humor pulling away... a present I got for my 53rd birthday..., I can't do that

I know Mouser ships to Paris. There is even a Mouser France, or Farnell, and many others like RS Parts. But this my point exactly. It’s just not financially worth it to pay $5 for a transistor

Sorry if I'm late to the party, Just wanted people to know the kits are still available on eBay and they work great. I just put one into my Tektronix 224 and it is performing exactly as advertised.