TDS6604 restoration - Page 1
Forum section: electronics / testgear

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 05, 2017, 09:10:21 pm
content: Hi guys!Trying to restore a Tektronix TDS6604. Has a cooked channel 1. Shows 'overload on ch1' everytime you start her up. So, I first assumed it would be a flunky RF relay (bit odd they run all over the board, go to the rf relays and run back to the AFE, but hey...). So, I figured I'd decouple the rf relays and if there were nothing left on the input, it can hardly overload anymore, can it.Well, no luck.So, I then check all the .. ahem.. late additions to the board and I noted the second picture, the leg of the transistor doesn't really seem to make contact. Well, that didn't pan out either. Been probing around a bit more on this side of the board, but I'm running out of stuff to do on this side. So, I'm considering taking the acq board out. Not a trivial task, not without risk either...So I was wondering: does anyone have a picture of the backside of this board? So I can estimate if it's worth taking it out?

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 07, 2017, 06:32:42 am
content: Hm.. this picture seems to suggest the whole acq board can be removed while keeping the front panel and rf switches attached. Might make it a bit easier

author: tautech
author_rank: Super Contributor
timestamp: December 07, 2017, 06:42:45 am
content: It's got 50inputs, right ?Go looking there, it's the most likely to have blown from excessive input which is usually only 5V max.

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 07, 2017, 07:19:49 am
content: Haven't found the termination yet. But that's very much on my todo lists, hence the desire to see the other side of the board.

author: tautech
author_rank: Super Contributor
timestamp: December 07, 2017, 07:26:49 am
content: Quote from: Ice-Tea on December 07, 2017, 07:19:49 amDo you need to ?Looking at your first pic, is each channel signal pass right across the board from the inputs ?Is the 50termination on the front panel before the rigid coax ?

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 07, 2017, 07:33:03 am
content: Quote from: tautech on December 07, 2017, 07:26:49 amOn the front panel? Don't think so, the coax there goes to the rf switches in the back. The other stuff there is for probe power, detection,... And I deconnected the rigid coax going from the rf switch to the board. So even if it were a dead short, it would now lo longer effect things.And if you'd terminate at the input, that would be a humongous stub after the input, no? I'm guessing I'd find the termination close to the in AFE itself. If I'm unlucky inside the AFE chipset

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 07, 2017, 08:13:48 pm
content: Eh, decided I don't have the time. Going to close her up and toss it in an auction on eBay. My guess is one of the AFE's is toast, it's not like I can just replace that anyways. I'll update this post with a link. Anyone interested in sparing me the trouble of putting money in EBays pockets: let me know.

author: nctnico
author_rank: Super Contributor
timestamp: December 07, 2017, 09:42:57 pm
content: Quote from: Ice-Tea on December 07, 2017, 08:13:48 pmPrice indication?

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 08, 2017, 08:08:03 am
content: Beats me. It's still a 3 channel 6GHz/20Gs/s machine. I have no idea what it would fetch at an auction. I guess 1500€ ex taxes/shipping/costs wouldn't be terrible.

author: Ice-Tea
author_rank: Super Contributor
timestamp: December 08, 2017, 09:25:01 am
content: Has softkey options SM ST JT3 RTE and JA3SM: Serial comm mask testingST: Serial pattern triggerJT3: Jitter/Timing analysisRTE: RT-Eye Serial Data Compliance and Analysis ApplicationJA3: Advanced Jitter analysis

author: snoopy
author_rank: Frequent Contributor
timestamp: December 09, 2017, 12:10:19 am
content: Tekhobbycap will buy it from you. He seems to have a lot of experience repairing Tek equipment and reselling them.