Telrad - common failures?

[Stu]

I seem to have two Telrads which have stopped working. Put new batteries in and nothing. Are there any common failures which happen, they seem pretty simple so am struggling to see what could go wrong!

[Zermelo]

https://stargazerslounge.com/topic/383688-telrad-failure

https://stargazerslounge.com/topic/319959-telrad-troubles

 

[johninderby]

Came across this on CN.

https://www.cloudynights.com/topic/379902-diy-telrad-repair/

[Stu]

Thanks all. Those threads give me something to go on. I’ll report back if I have any success. Thank you🙏

[Mr Spock]

Eeek, I hope mine doesn't fail. I seem to have an equipment jinx at the moment.

[Stu]

Problem no 1 solved, that was a dodgy connection to the battery holder. Just need to re solder the wires and it should be sorted.

No 2 I suspect is the potentiometer but it needs further investigation.

Thanks all 👍

[HAsun]

Hello,

I have a telrad that fell off the scope and hit the ground and appears to have gone out of allignment ? has anyone experienced this problem ?

 

[Zermelo]

15 hours ago, Stu said:

No 2 I suspect is the potentiometer but it needs further investigation.

If it is a pot fault, then this is apparently the replacement:

but I can't see it on a UK site.

 

[Ian McCallum]

11 minutes ago, Zermelo said:

If it is a pot fault, then this is apparently the replacement:

but I can't see it on a UK site.

 

Farnell, CPC, Mouser, RS Parts, etc? 🤔

[Zermelo]

29 minutes ago, Ian McCallum said:

Farnell, CPC, Mouser, RS Parts, etc?

Yes, I meant the "official" part, on UK Astro sites. I'm sure there's a similar version here somewhere, but I wouldn't know enough about the specs.

[Ian McCallum]

2 hours ago, Zermelo said:

Yes, I meant the "official" part, on UK Astro sites. I'm sure there's a similar version here somewhere, but I wouldn't know enough about the specs.

It's a linear 20kOhm potentiometer. Less than a pound in some places. 

[Spile]

The pot does need to be switched of course.