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I bought a second hand Telrad which arrived in the post this morning so I've just had a chance to look at it. The ad pictures showed the reticle powered up, but at a slight angle which cut off the bottom of the 4° circle. I should have questioned it but didn't, because it's sometimes difficult to get this sort of thing to come out properly in a photo. With the Telrad in my hand it is quite obvious that at some point it has been left out in the sun and there is a burn mark across the bottom of the reticle which results in a "squiggle" across the bottom/under the projected 4° circle. This would have been blindingly obvious to anyone who had used the Telrad. On it's own this seems more of an aesthetic issue but I also notice that if the variable switch is "off" at the six o'clock position and "fully on" at the 3 o'clock position, then the reticle only starts emitting light once it is rotated to the 2 o'clock position. (So there is only the very small 2-3 o'clock range to adjust brightness.) For those of you who own Telrads is this small range normal or does it suggest that there could be additional damage to the diode/wiring behind the reticle so that it only works under (almost) full power?

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When new, the rheostat that controls the LED brightness is full range.  On older units, they tend to die and often only produce on/off with nothing in between.  I picked up a couple of units in this condition, but with perfect reticles, for $35 shipped for both with full disclosure by the seller.  I hope you didn't pay over $20 for yours.  If you did, and the seller didn't disclose the issues you've noted, you should ask for a refund including shipping both ways unless the seller doesn't want it back, in which case I'd be good with a refund of just the purchase price.  If you used Paypal, their buyer protection may be able to help you.

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I've just had a quick check of mine in a darkened cupboard, not truly dark, but reasonable.

My power switch is also off at 6 o'clock and fully on at 3 o'clock, but my reticule starts to become visible, though very very dim at about 11 o'clock and gets progressively brighter as you turn it towards 3 o'clock.

Have you checked your battery? An almost exhausted battery might explain the not lighting up behaviour.

Hope this helps,

Ade

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I know that the seller should have disclosed the problem with the reticule, but if its any help you can get Telrad parts from 365 Astronomy.

https://www.365astronomy.com

Search for "Telrad" and it should show you results for the finder itself, replacement potentiometer, replacement glass, replacement reticule and other related parts and accessories.

Ade

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Thanks, guys. There was no disclosure of either issue prior to sale, I discovered them when taking the Telrad out of the box and turning it on. New batteries don't change the "on point" and the cost of replacement parts would take the total cost up to the point where I could have just bought a new one.

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1 hour ago, Ricochet said:

Thanks, guys. There was no disclosure of either issue prior to sale, I discovered them when taking the Telrad out of the box and turning it on. New batteries don't change the "on point" and the cost of replacement parts would take the total cost up to the point where I could have just bought a new one.

Ask for a price adjustment based on the cost of parts (and shipping) to do the repair if the seller isn't willing to do a full refund.

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I've sent it back for a refund. However, the short time I had it was enough to find that I quite liked the circles rather than a dot and also having all the adjustment knobs on the front in a nice easy to access location. With that in mind is there any other finder aside from the rigel that I should consider? With respect to the rigel is there any pros for choosing it over a telrad other than the smaller footprint? 

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20 minutes ago, Ricochet said:

I've sent it back for a refund. However, the short time I had it was enough to find that I quite liked the circles rather than a dot and also having all the adjustment knobs on the front in a nice easy to access location. With that in mind is there any other finder aside from the rigel that I should consider? With respect to the rigel is there any pros for choosing it over a telrad other than the smaller footprint? 

I have both and prefer the 4 degree circles and generally better parallax control of the Telrad over the Rigel.  However, the Telrad won't fit on short/small tubes, it's mainly good on Dobs, so the Rigel is my go to for the smaller OTAs.  The circles are thinner and harder to see on the Rigel and they tend to shift a bit with respect to the sky as you move your head about.  It does have a built in blinking feature which is nice that is lacking on the Telrad.  The batteries corroded in my original Telrad, destroying the LED in some manner.  Replacing the holder didn't help.  I'm still on the original lithium button cell that came with my Rigel 17 years ago without corrosion, so there is that.  You need to check the AA batteries regularly in the Telrad to catch corrosion early.

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3 minutes ago, Ricochet said:

Thanks, @Louis D. Sounds like the Telrad is the way to go given I've got the space. Would you say that the additional Telrad pulser would be worth adding? 

Not really.  If the dimmer is working properly (as it does when new), it can be dimmed to such a low level that pulsing is not necessary.  My used replacement units require me to flip the reticle on and off manually because it's running at full brightness.  You have to merge the view through both eyes for best usage, but a super bright reticle in one eye is still a problem even then.

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I've got a couple of telrads, one with a pulser and one without, and like them a lot so I also got a Rigel finder for where I can't or prefer not to fit a telrad.

The pulser is sometimes helpful but it's a marginal gain and often I don't use it at all in a session.

The Rigel is also good, small and light so better for smaller scopes. The controls are in the front if the Rigel which at first I thought was not clever but when you have your eye up to it it is ergonomically easier to reach and adjust controls on the front than on the back.

For the record my pulsating telrad lights up initially at about 10 o'clock and my other one lights up from about 8 o'clock(!) but both have a good range of smooth adjustment.

 

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