Tektronix 453 question.

[taithesamurai]

I picked up a Tektronix 453 and 454 from a guy off in my local area.The story behind them is it was from a place that re-calibrates test equipment.He told me 25 USD for each unit and these would be the best for me to repair and learn on.The unit 453 has a tag on it that says "Do not power up scope" and "Take out H.V assembly and wash interior boards". I did some reading and it said the H.V. boards attract a lot of dust. So my question is does washing the board mean physically washing it with water or some cleaner or does it mean getting a brush of some sorts and pressured air and blowing the dust off?

[Armadillo]

I have Jetted with water and scrub it at the same time before [oscilloscope boards].

Just dry it up that's all. Even micron electronics like wafers are washed with DI water donkey times. Nothing to worry about. But some common sense required, like humidity sensor cannot be wetted. Open carbon like potentiometer needs extra drying and anti-corrosion treatment after.

I am referring to boards that are so dirty and so dusty OR laden with spills etc..

But you need to judge it yourself. 

[taithesamurai]

Thanks for reply. I read somewhere on a old Atari service book that techs used to clean boards with 409 cleaner and that's what really confused me.

[james_s]

I typically use Simple Green or Oil Eater, scrub with a brush, rinse off in the sink, and then depending what it is sometimes a wash with isopropyl alcohol and then let it dry thoroughly. If your tap water has a lot of minerals then it's better to use distilled water but the water out here is fine.

[Tony_G]

It's not uncommon for people to wash boards in the dishwasher and then dry them in the oven. I haven't been able to bring myself to go that far but I have done water and IPA along with drying.

TonyG

[David Hess]

I prefer hot water with a little bit of dish soap or TSP and then rinsing with distilled, deionized, or reverse osmosis water before drying with an air compressor.

Potentiometers and most switches should be lubricated.

[james_s]

It's not uncommon for people to wash boards in the dishwasher and then dry them in the oven. I haven't been able to bring myself to go that far but I have done water and IPA along with drying.

TonyG

When I was repairing a lot of classic arcade game hardware I occasionally ran an entire CRT monitor through the dishwasher complete prior to starting work on it. After removing the upper rack, a 19" monitor would just fit. Games that had spent a portion of their lives in smokey bars had a disgusting sticky layer of tar all over everything and then dust would stick to that. The monitor would come out of the dishwasher looking brand new at which point it was much more pleasant to work on. The trick was to use only a tiny bit of detergent, put a blob of hot glue over the focus and screen controls to keep water out of the divider, remove the cardboard insulator over the back of the neck board, and then let everything dry thoroughly for several days before applying power.

I've washed quite a few logic boards that way as well, although you have to be careful because it will remove some of the solder mask on some. I find that washing in the sink by hand is safer.

[taithesamurai]

 I washed my iPod nano like 6 times let it dry for 3-4 weeks and it has never failed me haha.It really makes sense you can wash the board just don't power it on for a while and dry with a fan for a few weeks.Thanks for reply.