Free(US): Tektronix 464 with DM44 Digital Multimeter parts or repair. - Page 1
Forum section: electronics / general

author: PoDuck
author_rank: Regular Contributor
timestamp: February 13, 2018, 04:41:36 pm
content: I got my hands on a non-working, but inexpensive enough to gamble on, Tektronix 464, assuming I would have to do something to it, but since I the screen came on, and I saw a dot, I assumed it would be in the low voltage section that I would find the problem. Once I got it home and opened up though, I found a wire that looked like it got a bit warm, so I started following it, but it went under the top high voltage shield. I opened up the top shield, and started seeing major smoke residue all over the place. It was bad enough that it made it difficult to find the first obvious signs of damaged components, which were on the fan control board. The smoke had just billowed up into that high voltage section. Realizing that the fan being bad would not cause there to be no trace, I started looking deeper. I found more signs of smoke damage coming out of the CRT housing.Needless to say, at that point, I didn't feel up to pulling it apart far enough to see what smoked inside that compartment. I'm not sure if the two problem areas are connected. It could be that the fan blew, and someone kept using it and it overheated and blew something else.Anyway, It's a pretty old scope, so my interest in repairing it doesn't extend to tearing it down that far, so I am willing to send it off free to someone who is willing to pay shipping, or wants to pick it up in Peru, Indiana (USA). I considered putting it up on Ebay for parts, but figured there might be someone here that could find use for it.I've attached pictures of the damage I have found.

author: james_s
author_rank: Super Contributor
timestamp: February 13, 2018, 11:21:04 pm
content: The black residue around the HV wire looks like dust, HV stuff typically attracts a coating like that, it could be smoke from the other fault (that resistor clearly burned up) or it could be particulate from diesel engines or other airborne pollutants. I would not automatically assume anything is wrong with the HV section.

author: PoDuck
author_rank: Regular Contributor
timestamp: February 14, 2018, 02:50:40 am
content: Considering that there is smoke going down that hole too, on the shielding, not just on the wire, and I see no smoke trail from the fan board toward the front of the CRT where that hole is, I am skeptical. Plus, the fan board shouldn't stop traces from showing up, where something wrong in the HV section would. Plus, if that fan board went kaboom, it probably means the fan motor is pulling too many amps and needs replacing.Anyway, my triage nurse of a gut tells me that I shouldn't get too involved in it, because it's going to be a lot more time than I intended to spend on it, and once I start, I won't be able to stop myself.It would be a good project for someone with a little time though. I would bet it isn't going to be too much of a brain teaser problem, as much as a time consuming problem, since stuff that lets out smoke tends to be easy to find.

author: Brumby
author_rank: Unknown
timestamp: February 14, 2018, 02:59:23 am
content: Quote from: PoDuck on February 14, 2018, 02:50:40 amA lot of us have been there.At least you have had the wherewithal to realise the folly ofnotwalking away.

author: Kalin
author_rank: Regular Contributor
timestamp: February 18, 2018, 02:57:10 am
content: If you would consider shipping it to Canada I would be interested. Shoot me a pm with a weight and i will check what shipping fees would be and see if I can sneaking past SWMBO lol.Sent from my SM-G930W8 using Tapatalk