The Museum of HP Calculators

HP Forum Archive 09

[ Return to Index | Top of Index ]

HP71B Modules
Message #1 Posted by Laurence Carr on 16 Sept 2002, 2:32 p.m.

Hi

I recently acquired a 71B with 2 modules labeled "M109A/M198 1 of 2" and "M109A/M198 2 of 2" . They also have a label saying "HTI-SD-0113.00 Made in England". Does anyone know what these are?

Laurence Carr

      
Re: HP71B Modules
Message #2 Posted by Chris Catotti (Florida) on 16 Sept 2002, 3:46 p.m.,
in response to message #1 by Laurence Carr

I believe they were used for the M109 FAMILY OF HOWITZERS to help calculate artillery fire. The M109A4 and M109A4+ are fully tracked, armoured vehicles used to provide close artillery support. The vehicles are air-transportable and carry a total of 36 rounds. The 155mm cannon is designated the (M185). The assembly comprises a breech ring, bore evacuator, muzzle brake and a tube cannon. The breech mechanism is a semi-automatic, screw block type, designated for separate loading ammunition. Breech opening and closing is accomplished by utilizing the energy of counter recoil and closing, by laminated torsion springs. Firing is accomplished by the mechanism (M35) which uses cartridge type primers, fired by a continuous pull percussion mechanism. The mount consists of a cradle assemble that mounts the hydraulic variable recoil mechanism, S.A. cam, recuperator, counter recoil buffer, upper and lower rotors, limit stops and dust shields. Pad and brackets are available for mounting the fire control instruments.

http://www.eme421.com/m109.html

      
Artillery Targeting
Message #3 Posted by Mike on 17 Sept 2002, 5:00 p.m.,
in response to message #1 by Laurence Carr

These are artillery targeting modules. If you do a catalog, you will see things like "target" and others that have to do with coordinates, etc.

I asked a military discussion forum once if they ever used the HP-71B and got an affirmative. The dates that the person said he used them matched the era of these machines.


[ Return to Index | Top of Index ]

Go back to the main exhibit hall