7 replies to this topic

[Dave Novoselsky]

Found one of these st a local “give me whatever you want for it” charity event. Everything looks pretty nice on the scope so I bought it for my 8 yr old grandson to enjoy. I know very little about the Jason brand or this model in particular. Can someone tell me who the actual producer was?

Edited by Dave Novoselsky, 12 May 2024 - 02:20 PM.

[Russell Smith]

Hi Dave,
It's probably Towa. Look for a circle with a T in it on the focuser. The one with the flip up finder? I had one and liked the mount for a 60mm Pentax. They seem to have a following.
Cheers
Russ

[Dave Novoselsky]

Thanks

[Pete W]

Dave:

 

If it is a Towa Jason 313 with the flip finder, here's the instructions for aligning the flip finder with the main scope.  

Attached Files

•  Jason 313 reflex finder instructions.pdf   241.27KB   34 downloads

[SkipW]

I also picked up a Jason 313 from an estate sale a couple of months ago with the intent of giving it to my grand nephew. Now that the eclipse is over and I've worked through most of the deferred obligations that piled up while preparing for it, I can pay it some attention.

 

So far, I've been accumulating replacement parts - I found a couple of slow motion bendy-stalks that fit at a different estate sale for $1 (no telescope there, just the two stalks with knobs in a bin of miscellaneous unidentified doohickies), and a .965 to 1.25 adapter from ScopeStuff so an extra diagonal and some eyepieces I have on hand can be used with it - it came with only one EP and no diagonal.

 

I cleaned the old grease off the RA worm and wheel, and re-greased it with SuperLube, and it operates quite smoothly now. The dec slo-motion is already pretty smooth, so I'm leaving that alone, at least for the time being.

 

Does anyone know how to take the lens shade off? I'd like to clean the objective (I know how to clean optics). It's dusty and I don't want him to be tempted to try, but haven't been able to remove the shade or the cell after a few non-forceful attempts. There are no obvious retaining screws; are these threaded on? Something else? (Please, please, don't be glue!)

 

I'd like to have a copy of the manual for it if anyone has an extra, or a scan. Many thanks for that doc for the finder, Pete! Got any others? The reflex finder is pretty cool!

Edited by SkipW, 13 May 2024 - 09:19 PM.

[Pete W]

Skip:

 

I found the 313 to be a fun scope to use.  The field of view of the reflex finder is a bit tight - if I recall it was only  2 or 3 degrees - making it a challenge to find things, but a red-dot finder worked well to get objects in the finder field of view.

 

I have a pdf of the complete manual, but at 3.4 Mb it is too big to post.  If you private message me an email address I can send it along to you.

 

Pete

[SkipW]

Thanks, Pete. I sent you a PM.

[SkipW]

I also picked up a Jason 313 from an estate sale a couple of months ago with the intent of giving it to my grand nephew. Now that the eclipse is over and I've worked through most of the deferred obligations that piled up while preparing for it, I can pay it some attention.

 

So far, I've been accumulating replacement parts - I found a couple of slow motion bendy-stalks that fit at a different estate sale for $1 (no telescope there, just the two stalks with knobs in a bin of miscellaneous unidentified doohickies), and a .965 to 1.25 adapter from ScopeStuff so an extra diagonal and some eyepieces I have on hand can be used with it - it came with only one EP and no diagonal.

 

I cleaned the old grease off the RA worm and wheel, and re-greased it with SuperLube, and it operates quite smoothly now. The dec slo-motion is already pretty smooth, so I'm leaving that alone, at least for the time being.

 

Does anyone know how to take the lens shade off? I'd like to clean the objective (I know how to clean optics). It's dusty and I don't want him to be tempted to try, but haven't been able to remove the shade or the cell after a few non-forceful attempts. There are no obvious retaining screws; are these threaded on? Something else? (Please, please, don't be glue!)

 

I'd like to have a copy of the manual for it if anyone has an extra, or a scan. Many thanks for that doc for the finder, Pete! Got any others? The reflex finder is pretty cool!

Answering my own question, careful inspection with a bright light revealed threads on the inside of the lens shade near its base, and applying more torque to it (with bare hands) than I had before, it unscrewed. The cell is also threaded on to the tube. The lens cleaned up nicely without having to remove it from its cell!

 

I recently 3D printed a lens cap at our local library. They offer "maker space" to library card holders, provide links to free software suitable for creating the necessary models (I used OpenScad), and make their printers (laser cutters, small CNC mills, etc.) and some hand holding available at no cost except for filament they provide at $0.10/gram (no charge if you provide your own filament). The lens cap used 20.8g of black filament, so $2.08, and worked on the first try.  

 

With the lens cap done, some inexpensive eyepieces acquired at the Okie-Tex swap meet, the other bits I'd been gathering, and some cleaning and TLC, the 'scope is ready for his birthday in about a month.

Edited by SkipW, 21 November 2024 - 02:14 PM.