First post

[WolfMax]

Hi All

I'm Colin, and I found your forum purely by accident but reading some of the posts it ignited my interest in lasers again. So I thought I'd show you my first laser (and at the moment, only laser), that I built over 25 years ago.



Not much to look at I know, but I had a very limited budget and not much in the way of knowledge on the subject (still don't).




PSU is an old Maplins kit from the 80's I'm going to add a proper power socket (kettle lead type)




Laser tube from Maplins too (shame they don't do them anymore) and I bet that has stirred up a few memories!




NEC GLT172 HeNe




It's ALIVE!!! Not bad for a 25+ year old gas laser! I have no records for the hours of use but it is likely less than 100 - 150


I did make a lissajole figure unit for the front but it has lost one of its mirror mounts so I'm not going to use it anymore. But for anyone interested in a simple control circuit for one:



It uses 4 1.5v AA batteries tapped in the centre to produce a +3v, -3v, Gnd arrangement. and a reversing switch for one of the motors. A simple 3.5mm stereo audio cable (like those used between PC's and speakers) can then be used to feed the motors so they don't have to be permanently wired.

My plan now is to obtain a 'cheap but reasonable' display unit like a KAM Laserscan unit for example, to use as a base for experimentation and possible upgrade path (if it is indeed possible). Any and all suggestions on this will be gratefully received.

It is just a personal hobby and I'm not planning on doing any public displays but I do understand the need for safety none the less.

Anyways, that's me so far.

All the best

Colin

[WookieBoy]

Hey Colin.

Welcome to PL!

Where abouts are you based? I'm guessing in the UK due to your references to Maplin?
If you fill in your location in your profile, you may find you're pretty close to other members who can pool resources... Also, there may be a LEM near you coming up!

Anyway, like I said welcome.... and be aware your wallet is going to hate you soon enough!

[csg]

Hello Colin and welcome. I've only been on here a little time myself but have already learnt an enormous amount, allowing me to complete building my first 2 RGB projectors.

The maplins kit brings back fond memories, in fact I think I used that very case to build my first sound to light "partylite" kit with my dad some 26 years ago. That kit was probably the best Christmas present I ever had!

[WolfMax]

.... and be aware your wallet is going to hate you soon enough!

Thanks for the reply, profile updated. As for the wallet, I own a 2003 Yamaha Vmax 1200 motorcycle so I already know about 'dented wallet syndrome'.

[WolfMax]

Hello Colin and welcome. I've only been on here a little time myself but have already learnt an enormous amount, allowing me to complete building my first 2 RGB projectors.

The maplins kit brings back fond memories, in fact I think I used that very case to build my first sound to light "partylite" kit with my dad some 26 years ago. That kit was probably the best Christmas present I ever had!

Thanks for the reply. I must confess the case came about 10 years ago (I was running it with the PSU in some old case with the bare laser on top before! Not good!!). But an RGB projector is the plan. Not looking for power as it's not going to be used for displays, just for me to have fun with. Hopefully that will keep the cost down!

[LaNeK779]

Hi Colin and wellcome!

A suggestion if i may, make your own rgb! It will be a fun process and you will learn a lot

just to give you an estimate of things, costs etc

There is a three diode kit (all single mode = superb beam specs) available from dtr https://sites.google.com/site/dtrlpf...gb-diode-budle
There are diode mounts, lens holders, dichro holders and various brass parts from dave http://lasershowparts.com/store/inde...&productId=302 and http://lasershowparts.com/store/inde...&productId=302
There is the magic electricery, optics and galvos from stanwax http://shop.stanwaxlaser.co.uk/
Laser diode drivers are available from drlava, badpip, lasertack and other sources

All you need to do is find an ali plate, some power supplies and bold it all on top. The powers are low, so you will not have to worry about elaborate cooling solutions, setting things on fire etc. All you will have to watch out for is not to place your eye on the wrong end of a beam

Then you will have a killer little unit that due to tight beams will appear much brighter than its rated wattage. plus it will be free from the dpss lag and problems and it will save you all the trouble of beam correction and shaping that is needed with the higher power blue and red diodes.

Then you will have to decide on what software and dac to use, there are cheaper sollutions (sub 200usd for both) and more expensive ones (over 4000usd), so plenty of choice there

you will find that the people here are friendly and helping if you are willing to listen. Plus, the Uk PL crew is awesome. if you hear anything about a uklem, just go!

cheers,
chris

[absolom7691]

Not looking for power as it's not going to be used for displays, just for me to have fun with.

I truly believe you, however, I said the same thing when I built a 1/4W RGB projector. I didn't care for the lack of power in my red so I bought a brighter one. Then my blue and green were too weak. I bought brighter ones to match the red. Then the red wasn't bright enough to match again.... Sure, I could have attenuated my lasers, but that's no fun! Needless to say, I have spent a ton more $$$ since joining.

Welcome to PL!

[Jem]

Hi Colin

...And welcome to PL

Loving the little HeNe, there's nothing quite like the beautiful beam profile you get, even if it is only a few mW. Nice to see we're getting a few more UK members crawling out of the woodwork. Best advice I can give is to try and get yourself along to one of our UK laser meets.

Cheers

Jem

[Laserhobbit]

Hi Colin,

I think so many of us started with the Maplin HeNe. Mine has lead me on the most exciting journey of my life and all around the world working and "playing" with lasers. Long gone are the days of mirrors glued on old speaker cones covered in burst balloons, but the magic never fades ( excuse the pun ).

Welcome and I hope to catch up with you at a LEM sometime.

Cheers


Steve

[WolfMax]

Thanks for all the welcomes.
I will try and get to a LEM if I can as they sound like they could be very informative.

I thought I'd just add another picture I took just now of the spot from 2m away.



It is around 4mm at this distance (2mm at 1m) as there is no collimating optics involved (any suggestions?). There is also a 'halo' effect where coherent light is escaping from the laser that may have been bounced off the internal glass structure of the laser, becoming strong enough to get through the mirror but in an unfocused manner.

I found an old NEC product catalogue from 1985 which lists the laser. It is 0.8mw at 632.8nm. Random polarization with a beam diameter of .66mm at 1/e^2 points (whatever that means)

Anyhow, though it might interest people.