Results 1 to 5 of 5

Thread: CTI 3200-142 AOM, anyone have specs?

  1. #1
    Join Date
    Aug 2009
    Location
    Bristol, England
    Posts
    333

    Default CTI 3200-142 AOM, anyone have specs?

    Hi all,
    I have just spotted that surplusshed have brand new CTI 3200-142 AOM crystals including bragg mounts for $14ea!

    This raises two obvious questions:

    1) Does anyone know what the RF parameters are so a driver can be cooked up.

    2) These are specified as being coated for 442-488nm, does anyone know how far outside that range it will be possible to go before losses rise unacceptably? Is there any chance that 532 might still work for example?

    edit: http://www.crystaltechnology.com/pro...odulators.html

    Summary:
    For the - 141 (The - 142 is not listed).
    RF is 200Mhz at up to about a watt.
    Active area is a bit on the small side so some optics in and out will be required, still no idea if they will work at 532, going to have to experiment. Pity they are not 3080's.
    Quoted efficiency is not particularly great, 80% if you can get a 100um beam waist....

    Regards, Dan.
    Last edited by DMills; 08-31-2010 at 15:02. Reason: Found some data.

  2. #2
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,186

    Default

    The AR coat is optimized V coat for blue, at 532, whats 2-3% more among friends. I have yet to meet a non 50 ohm AOM.

    Experimental Notes:

    Minicircuits VCO followed by whatever the modern version of a MAR-6 is, followed by a 1 dB pad by one LEVEL 7 TUF series mixer for OK modulation, or TWO TUF series mixers for better extinguishing ratio, followed by a another 1 dB pad followed by a MAV-11, followed by this:
    ( The Pads terminate the mixers , in the most delightful and proper way)
    (Note for Young folk, if you have never wired at VHF or RF , don't start with this!)
    Attached Thumbnails Attached Thumbnails 200Megahurtz.bmp  

    Last edited by mixedgas; 08-31-2010 at 15:38.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  3. #3
    Join Date
    Aug 2009
    Location
    Bristol, England
    Posts
    333

    Default

    About what I was planning, but I like making about 2W then adding a 3db pad at the output so the driver is somewhat protected from VSWR in the event of a fault.

    You can forgo the mixers by modulating the supply rail to the final amplifier (Old school AM transmitter style), which also means the final can be run class C.

    Double sided board with solid ground plane and its all good.

  4. #4
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,186

    Default

    Um, Isomet AOs are quite sensitive, you might want to forgo the the sliding rail class C and use the mixer, or you WILL see some ghost. NEOS likes to get their drivers 40-60 dB down.
    I really doubt you need the full .7 watt drive by a long shot.

    Interestingly enough, Digikey has:

    631-1184-1-ND

    At 200 Mhz, however getting from 3.3 into 600 ohms to 13 dbM into 50 is still going to require a few MAVs or ERAs. MMICs are so cheap there is no reason to use discrete parts.

    I'd keep the distortion down, AOs really, really, like sine drive.

    PM me off list, I might have a 24V CATV block that I can part with cheap. I'll have to hook it to the PTS250 and see how much drive it needs at 200 for a watt.


    PS, if this is Greek to anybody reading it, the yearly ARRL or RSGB handbooks are at most libraries or show up for 6$ used on Amazon.

    Steve
    Last edited by mixedgas; 08-31-2010 at 15:50.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  5. #5
    Join Date
    Aug 2009
    Location
    Bristol, England
    Posts
    333

    Default

    I would need to lowpass that module, it does HCMOS square wave output by default, not exactly a hard problem....

    There are actually some MMICs that will make a watt at -1db point!

    Regards, Dan.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •