WANTED: TENMA 72-465 Multifunction Counter Manual/Service Manual - Page 1
Forum section: electronics / repair

author: Shock
author_rank: Super Contributor
timestamp: May 22, 2015, 11:51:32 pm
content: Looking for the Tenma 72-465 Multifunction Counter Manual and Service Manual or Schematics. Preferably free, electronic version is fine, please let me know if you can assist or have one.

author: Andy Watson
author_rank: Super Contributor
timestamp: May 31, 2015, 09:00:54 pm
content: Bears an uncanny resemblance to an Elenco F100http://www.elenco.com/support/manuals

author: Shock
author_rank: Super Contributor
timestamp: June 01, 2015, 03:20:12 am
content: Looks close doesn't it, thanks for that. There is an extra button on the Tenma 72-465 "LF" thought that was a low pass filter at first but with in/out?

author: Andy Watson
author_rank: Super Contributor
timestamp: June 01, 2015, 09:41:01 am
content: You might have an updated version - the basic design seems to have been around for a long time. I have the F1000 - same case, including the L.F. in/out, but the trigger level is replaced by the prescalar input. Mine was bought as a Maplin "Gold" MF1000. These counter appear in several re-badged brands.

author: Shock
author_rank: Super Contributor
timestamp: June 01, 2015, 03:58:14 pm
content: Do you know what the LF in/out is?

author: Andy Watson
author_rank: Super Contributor
timestamp: June 01, 2015, 04:52:56 pm
content: NoI had always assumed that it was a low-frequency filter. I have just removed the case but it is not obvious how the switch is connected - only that it switches input to something else, or not. There is a 0.47uF capacitor in series with the input - I thought the switch might short it out to pass D.C. - but it doesn't beep-out and I can't see where the tracks go.The circuit board is labelled HC-F1000lf, so it looks like Hung Chang were the actual manufacturers.

author: Andy Watson
author_rank: Super Contributor
timestamp: June 02, 2015, 10:58:17 pm
content: By chance, whilst searching for something else, I found Maplin's original instruction book for the MF1000. All it says about the LF switch is:Low pass filterapprox 100kHz, - 3dBapprox 150kHz, -3db at 20dB ATT

author: Shock
author_rank: Super Contributor
timestamp: June 03, 2015, 07:05:43 am
content: Here is a photo of the controls of a similar TENMA 72-465 to the one I have. Does the Maplin MF1000 have matching controls in that manual, namely LF instead of LPF? If so that might be the manual I need, possible to get a copy of it? Send me a PM if required.

author: Andy Watson
author_rank: Super Contributor
timestamp: June 03, 2015, 12:19:25 pm
content: No, it's not looking goodI've attached a scan of the MF1000 operators manual. The front panel is exactly as it appears on page 4, plus the Maplin logo. I believe this is the same model but with the LF and Attn buttons swapped:http://www.radiomuseum.org/r/hungchang_multifunction_counter_hc_2.htmlThe PCB in my counter bear the Hung Chang label HC-F1000-LF(6).I've also attached the Elenco manual for the F1000 - it has the schematic for the model without the LF button. Aside from the LF button it appears to be very similar to my MF1000.

author: Shock
author_rank: Super Contributor
timestamp: June 03, 2015, 03:20:01 pm
content: Thanks for that, seems almost comical it's labelled out/in, hopefully eventually someone will show up with the Tenma manual but in the meantime at least I have something to work with, cheers.

author: Shock
author_rank: Super Contributor
timestamp: November 12, 2015, 01:51:21 pm
content: Necro bumpStill looking for the manual specifically an electronic copy of it.

author: tonyalbus
author_rank: Super Contributor
timestamp: June 02, 2020, 02:17:37 pm
content: Quote from: Andy Watson on June 03, 2015, 12:19:25 pmThanks!Helpful, looks like my Dynatek DFC1000 but pcb was labled HC-F1000LF too !