TAL 2M Telescope Beginner Questions

[John_D]

I've recently bought a TAL 2M telescope off eBay. It's 1200mm / 48" long and looks as if it hasn't been used much recently. My plan over the next few weeks is to assemble what I've got and see if there's anything missing or needs fixing. Some of the controls seem a bit stiff but hopefully that's just a bit of re-greasing that's required. I'm not sure of the date of manufacture as there's precious little paperwork but the labels inside the box have the text "12.93" on them which could be a date I suppose. I imagine there's a serial number somewhere but I haven't really looked.

I've already found lots of good stuff on these forums ( thanks! ) and have downloaded the manuals but I have a few questions and I'd be grateful if anybody could point me in the right direction.

1. Using 12v AC 50Hz for the motor is slightly unusual. I assume that the "electric clock drive" referred to in the manual locks to the 50Hz to give the right rotation speed? The power supply that I have is marked "Douglas Louth Eng".
2. The service manual that I downloaded mentions a "Control Panel" with speed selection buttons. That's not mentioned in the list of items in either box, was it an option or a later addition? The service manual states "If the control panel is provided the car's mains or storage battery 12 V can be used through the car's cable." which implies that it was an option.
3. The standard focuser seems to have been replaced with a "Sky's the Limit" unit. The original focuser came with it, is worth putting the original back on?
4. In most of the pictures of these telescopes that I've seen the OTA and stand are white but mine is a rather fetching blue. It doesn't look to have been painted and I'm not bothered really but it would be interesting to know the history.

Thanks
John

 

[John]

Hello and welcome to the forum 🙂

I can't answer all your questions but I might be able to help with a couple of them.

The blue painted versions were the very early ones. Sometimes known under the branding "Sovietski". Later the colour scheme changed to the more traditional white tube with black fittings and the brand name "TAL" was used. 1993 may well be the year of manufacture explaining the 12.93 printing on the labels.

The early ones had a simple rack and pinion focuser but I seem to recall that they did not quite use the normal 1.25 inch fitting. The supplied eyepieces were slightly larger in diameter. This caused issues when other brands of 1.25 inch eyepieces were going to be used which might explain the replacement focuser on your scope.

There is quite a lot of information around the internet on these scopes but you have to dig for it. 

[michael8554]

1. Yes that's the Clock Drive. Centuries ago mounts were driven by clockwork systems called Clock Drives. 

3. As John recalled, early TAL 1M's came with a non-standard diameter focuser, larger than the 1.25" standard. The eyepieces that came with the mount were good quality though.

A TAL 1M was my first scope, and I struggled with star hopping using the Setting Circles.

Until I discovered the setting circles were for the Southern Hemisphere, meaning they were "backwards" for the northern hemisphere !

Michael

[doublevodka]

12 hours ago, John_D said:

I've recently bought a TAL 2M telescope off eBay. It's 1200mm / 48" long and looks as if it hasn't been used much recently. My plan over the next few weeks is to assemble what I've got and see if there's anything missing or needs fixing. Some of the controls seem a bit stiff but hopefully that's just a bit of re-greasing that's required. I'm not sure of the date of manufacture as there's precious little paperwork but the labels inside the box have the text "12.93" on them which could be a date I suppose. I imagine there's a serial number somewhere but I haven't really looked.

I've already found lots of good stuff on these forums ( thanks! ) and have downloaded the manuals but I have a few questions and I'd be grateful if anybody could point me in the right direction.

1. Using 12v AC 50Hz for the motor is slightly unusual. I assume that the "electric clock drive" referred to in the manual locks to the 50Hz to give the right rotation speed? The power supply that I have is marked "Douglas Louth Eng".
2. The service manual that I downloaded mentions a "Control Panel" with speed selection buttons. That's not mentioned in the list of items in either box, was it an option or a later addition? The service manual states "If the control panel is provided the car's mains or storage battery 12 V can be used through the car's cable." which implies that it was an option.
3. The standard focuser seems to have been replaced with a "Sky's the Limit" unit. The original focuser came with it, is worth putting the original back on?
4. In most of the pictures of these telescopes that I've seen the OTA and stand are white but mine is a rather fetching blue. It doesn't look to have been painted and I'm not bothered really but it would be interesting to know the history.

Thanks
John

 

Not jealous at all... 😂 I will own one of these one day

12.93 likely refers to the date of manufacture, certainly a lot of them seem to have been made in the 90's so that would make sense.

Point 2 - from what I've seen the control panel was an optional extra with a car power supply

Point 3 - stick with the current focuser if it works ok, was likely replaced for a reason, although there's no harm in switching back to the original if you really want to 

Point 4 - they are most commonly white, but there are some blue ones about, i've only ever seen the 2M's in that colour scheme, the older ones anyway, newer TALs seem to be all blue

[John_D]

Thank you all for your responses. 

It makes sense that the blue ones are earlier. The label inside the box is marked as a "TAL" but with the 'L' in Cyrillic - "TAЛ" ( That may not display correctly! ).

I've had a quick measurement with the vernier calipers this morning and yes, the TAL eyepieces do seem to be slightly oversized. The 'normal' 1.25" eyepieces that I have for my 70mm refractor are just a touch under 1.25" whereas the TAL ones are a touch over. The TAL ones won't fit in my refractor focuser and my existing ones are a bit of loose fit in the TAL focuser.

Interestingly, on further inspection, none of the supplied TAL eyepieces or the 4x Barlow lens will fit into the replacement focuser that's currently on the scope so it looks as if the first job is to replace the original focuser and take it from there! I was concerned that my camera adapter would be too loose a fit but fortunately part of the standard TAL focuser unscrews to reveal an M42 thread which fits my Nikon M42 adapter very nicely.

After I posted I did a bit more digging and I found this post from 2010 - https://stargazerslounge.com/topic/57026-the-tal-2-m-newtownian-reflector/ - which was also very informative especially regarding the motor drive.

doublevodka - I'm sure that you know that these come in two very substantial plywood boxes. These are currently lurking in our utility room and SWMBO has already asked the dreaded question - "... and where exactly are you going to keep that?" 😁

 

[michael8554]

My TAL-1M was given to my wife by the school she worked for.

They had it for years but had never used it.

I went to collect it and was presented with two stout wooden boxes stencilled with Russian writing.

The steel tubing inside looked like parts for a shoulder-mounted missile launcher !

Michael

[John]

I bought a new TAL100 refractor in 1999 and that arrived in a single but massive wooden case. The scope had come overland from Siberia but despite some gouges in the wooden case, arrived in good shape. I was on holiday when it was due to arrive in this country so I arranged for the delivery to be to my work address and forgot to tell any of my colleagues. When it arrived they said they thought that a small coffin had been delivered for me ! 😁

The thing with TAL's is that you suspect that they will still be around and working long after we have shuffled off ...... 😉

[doublevodka]

On 31/08/2023 at 11:40, John_D said:

doublevodka - I'm sure that you know that these come in two very substantial plywood boxes. These are currently lurking in our utility room and SWMBO has already asked the dreaded question - "... and where exactly are you going to keep that?" 😁

 

Very much aware and that's part of the appeal for me, I like the industrial look

I'm up the road from you in Ammanford so if it becomes too much for SWMBO give me a nudge 😂 mine live in the shed so it's not too much of a problem although I do get the occasional "why do you need 3 telescopes?"

Also since you are in the right area, if you are on Facebook take a look at https://www.facebook.com/groups/597841820359277 it may be of interest 👍

[John_D]

On 01/09/2023 at 13:21, doublevodka said:

Also since you are in the right area, if you are on Facebook take a look at https://www.facebook.com/groups/597841820359277 it may be of interest 👍

Thanks for the information. I'm not much of a social media person but I'd like to come along to some events.

I spent a few hours yesterday assembling the scope. It was surprisingly straightforward and the clock drive also seems to work OK with the ticking noise just adding to the overall "missile launcher" ambience!

Two small issues that I had were:

1. I put the original focuser back but the mechanism is a little sloppier that I'd like. More pondering is needed.
2. Fitting the finderscope was tricky. There are some dovetails near the focuser as can be seen in the picture but there seems to be no way of securing it properly. There are two grub screws on the dovetail which don't seem to do anything. More investigation is needed.

I also found a small plate in the box which gave a serial number and the date of manufacture as 1996 so the estimates weren't far off. The skies are meant to be clear tonight so hopefully I can give it a proper test.

[John_D]

Well the weather gods and my sleeping pattern finally got it together this morning and I had about an hour's worth of clear sky around 3.00 a.m. I had an excellent view of Jupiter and its 4 Galilean moons which is great as I hadn't had a chance to try the TAL out until now.

The two small issues that I had above:

1. The original focuser and the TAL eyepieces seem to work fine and focusing is OK, even the 4x Barlow ( although the image does get a bit soft with the latter ). 
2. I "fixed" the finderscope by adding some washers under the fixing screws on the dovetail to give a bigger area to secure it and by shimming with some bits of cardboard from a Weetabix packet ( other breakfast cereals are available ). That seems to work for now at least.

Next time I'll get the camera attached ...