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I bought a shiny new Telrad for my dob last week, and got round to fitting it yesterday evening. Managed to situate it nicely and then went inside and left my scope to cool down.  Then it fell off...

The 5ft fall on to the patio has completely destroyed it. But not the outside, only the inside... The battery pack is ruined and the reticle has come loose and ripped all the wiring out. I might be able to repair (well I have to try, I don't have the money for another one) but having only ever opened a Telrad once it has occurred to me I have no idea what it is supposed to look like on the inside or where anything goes. 

Would any Telrad owners possibly be good enough to send me a couple of photo's of the inside of their Telrad so I can get an idea how to rebuild and what to solder where? If anyone is feeling extra extra helpful perhaps they could tell me (possibly with the help of a ruler) specifically where the little reticle thing mounts in the housing?

Many thanks all.

Niall

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I usually find Google image search a good source.

https://www.google.com/search?q=telrad&client=firefox-b-d&source=lnms&tbm=isch&sa=X&ved=0ahUKEwihkrH_zpXjAhV8Q0EAHX4oDwQQ_AUIECgB&biw=1535&bih=768#imgrc=oZLVCZrB6NsHgM:

It turned up quite a detailed internal drawing that someone previously posted here on SGL, back in 2014 (Astrotux)

 

ss_telr4.gif

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Are all your wires still connected to the rotary switch? Getting in there looks to be the hardest part. I can't get a picture and I'm trying to see what goes where using the diagonal mirror. 

Wiring is as follows: 

Red: Battery pack + to reticule top

Black: Battery - to switch, 1 position clockwise from unused pin

White: reticule bottom to switch, 1 position anticlockwise from unused pin

1457122122_Telrad_Telrad50fc91389-ebfb-4646-b249-a606664e724a.thumb.jpeg.278d0060731c67d1d3e2c0f31644c495.jpeg

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48 minutes ago, Ricochet said:

Are all your wires still connected to the rotary switch? Getting in there looks to be the hardest part. I can't get a picture and I'm trying to see what goes where using the diagonal mirror. 

Wiring is as follows: 

Red: Battery pack + to reticule top

Black: Battery - to switch, 1 position clockwise from unused pin

White: reticule bottom to switch, 1 position anticlockwise from unused pin

1457122122_Telrad_Telrad50fc91389-ebfb-4646-b249-a606664e724a.thumb.jpeg.278d0060731c67d1d3e2c0f31644c495.jpeg

Thanks that's perfect those are the two measurements I need I can solder the rest. 

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Thanks everyone that's everything I need. Many thanks wish me luck! 

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1 hour ago, Ricochet said:

Good luck 

Thanks! Managed to get the front off and the diagonal out; from there I was able to solder (ish…) the back and white wires back on. Ordered a battery holder from ebay so hopefully just a case of attaching that and re-sighting the reticle and we're back in business! Well, after I've got some half decent sticky pads!

Not a mark on the outside. Must be made of the same stuff as Starbug from Red Dwarf...

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I was worried about the same thing when I first got my dob. I didn't trust that double sided foam tape. So rather than just adhere the base to my dob, I actually cut the base plate so that I could slide it in the dovetail mount on the dob and secure it with the screw. Been like that for two years and no incidents.

IMG_20170926_180651small.thumb.jpg.26fcc694f2fc45400fd48a2c2ce01cb3.jpg

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Or drill a couple of holes in the Dob and bolt the Telrad in place. That’s what I did after the sticky pads have way - twice.

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Cable ties are a quick and reliable method as well.

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If you don't want to make new screw holes then take off the mounting for the old finder and use one of the screw holes for the telrad.

Also, cleaning the area you plan to mount the sticky tape on with IPA (Isopropyl Alcohol) wipes from a pahrmacy will make it stuck much better.

How you get it fixed!

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