« previous next »
Pages: [1]   Go Down

Author Topic: My new project  (Read 6969 times)

0 Members and 1 Guest are viewing this topic.

Offline Mr JTopic starter

  • Regular Contributor
  • *
  • Posts: 93
    • Facebook mjssvt
My new project
« on: February 05, 2011, 03:07:18 am »
Found a old Simpson 710 Frequency Counter in the trash bin at work. Brought it home powered up okay but it was stuck on one frequency. After opening it up I heard a rattle from the crystal in the back. Tested the ICM7207 IC the crystal was connected to and zippo on the output, I took the crystal out and took it apart, bingo broken crystal. Have a new +/- 10ppm on order, hope it works.

What a great little unit from the 80's all though hole 74 series logic, small for the day. Still small today.
Logged
 

Offline Lance

  • Frequent Contributor
  • **
  • Posts: 317
  • Country: 00
  • Resistance if futile if R<1Ohm
Re: My new project
« Reply #1 on: February 05, 2011, 04:35:19 am »
Score. How do crystals like that break? Was it just a shock that broke it?
Logged
#include "main.h"
//#include <killallhumans.h>
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 19929
  • Country: gb
  • 0999
Re: My new project
« Reply #2 on: February 05, 2011, 10:12:41 am »
It looks like it.

I've never experienced it myself but I've heard crystals can break like that if handled roughly and overvoltage at the resonant frequency will probably cause it to shatter in a similar manner.
Logged
 

Offline Mr JTopic starter

  • Regular Contributor
  • *
  • Posts: 93
    • Facebook mjssvt
Re: My new project
« Reply #3 on: February 05, 2011, 05:54:47 pm »
yea I think it was shock that broke it, there is a bit of a dent in the corner of the housing and the crystal is right on the edge of the pcb. It's a fairly high frequency fundamental 6.553600 Mhz and the sub-straight is really thin. I order a custom one at ICM, mil spec made it thicker.
Logged
 

Offline saturation

  • Super Contributor
  • ***
  • Posts: 4787
  • Country: us
  • Doveryai, no proveryai
    • NIST
Re: My new project
« Reply #4 on: February 05, 2011, 08:04:32 pm »
Nice.  The counter looks to be in good shape, and good job with your quick and accurate troubleshoot.
« Last Edit: February 06, 2011, 02:57:57 pm by saturation »
Logged
Best Wishes,

 Saturation
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 19929
  • Country: gb
  • 0999
Re: My new project
« Reply #5 on: February 06, 2011, 09:03:42 am »
Quote from: Mr J on February 05, 2011, 05:54:47 pm
yea I think it was shock that broke it, there is a bit of a dent in the corner of the housing and the crystal is right on the edge of the pcb. It's a fairly high frequency fundamental 6.553600 Mhz and the sub-straight is really thin. I order a custom one at ICM, mil spec made it thicker.
I'm surprised you had to order a custom made crystal and couldn't find a standard part. My local supplier sells 6.5536MHz although they're only 30ppm so not good enough for your application.
http://uk.farnell.com/iqd-frequency-products/lf-a135a/crystal-6-553600mhz/dp/9712348
Logged
 

Offline PStevenson

  • Regular Contributor
  • *
  • Posts: 231
  • Country: gb
Re: My new project
« Reply #6 on: February 10, 2011, 10:54:27 pm »

it makes me sick to the stomach when I know beautiful things like that can just get thrown away by people!
I got an old tiny 15MHz phillips oscilloscope in a similar way, it was just an internal fuse that had gone.
Logged
I learned more from the EEVBlog than I did in school
http://youtu.be/s-TK0zaakNk
 Amp Hour Theme Song Full Version http://youtu.be/buKg2eAX4Z0
 

Offline Mechatrommer

  • Super Contributor
  • ***
  • Posts: 11713
  • Country: my
  • reassessing directives...
Re: My new project
« Reply #7 on: February 11, 2011, 03:36:08 am »
Quote from: PStevenson on February 10, 2011, 10:54:27 pm
it makes me sick to the stomach when...
thats what happened when you know too much ;)
Logged
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Offline PStevenson

  • Regular Contributor
  • *
  • Posts: 231
  • Country: gb
Re: My new project
« Reply #8 on: February 11, 2011, 09:20:22 am »

I just hope Darwin sorts those people out!
Logged
I learned more from the EEVBlog than I did in school
http://youtu.be/s-TK0zaakNk
 Amp Hour Theme Song Full Version http://youtu.be/buKg2eAX4Z0
 

Offline DavidJRobertson

  • Regular Contributor
  • *
  • Posts: 53
  • Country: scotland
    • davidr.me
Re: My new project
« Reply #9 on: February 28, 2011, 08:39:47 pm »
Quote from: Mr J on February 05, 2011, 05:54:47 pm
... the sub-straight is really thin...
*substrate.
Sorry just crap spelling pisses me off.
Logged
 

Offline JohnS_AZ

  • Frequent Contributor
  • **
  • Posts: 499
  • Country: us
    • About.me
Re: My new project
« Reply #10 on: February 28, 2011, 09:44:54 pm »
Quote from: DavidJRobertson on February 28, 2011, 08:39:47 pm
Quote from: Mr J on February 05, 2011, 05:54:47 pm
... the sub-straight is really thin...
*substrate.
Sorry just crap spelling pisses me off.

[I'm] sorry [, it's] just [that] crap spelling pisses me off.

Spelling:       A
Grammar:      F
Punctuation:  F

 :)
Logged
I'm either at my bench, here, or on PokerStars.
 

Offline DavidJRobertson

  • Regular Contributor
  • *
  • Posts: 53
  • Country: scotland
    • davidr.me
Re: My new project
« Reply #11 on: February 28, 2011, 09:55:35 pm »
Quote from: JohnS_AZ on February 28, 2011, 09:44:54 pm
Quote from: DavidJRobertson on February 28, 2011, 08:39:47 pm
Quote from: Mr J on February 05, 2011, 05:54:47 pm
... the sub-straight is really thin...
*substrate.
Sorry just crap spelling pisses me off.

[I'm] sorry [, it's] just [that] crap spelling pisses me off.

Spelling:       A
Grammar:      F
Punctuation:  F

 :)
Haha good point.
Logged
 
Pages: [1]   Go Up
« previous next »

Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf

 


EEVblog Main Site EEVblog on Youtube EEVblog on Twitter EEVblog on Facebook EEVblog on Odysee