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Products => Test Equipment => Topic started by: tkamiya on April 24, 2018, 01:25:03 am

Title: HP5335A why is the led cover removable?
Post by: tkamiya on April 24, 2018, 01:25:03 am
I've never seen anything like this before....

I was looking at new-to-me HP 5335A universal counter.  In 3 places on top edge of smoked acrylic, there are small black levers and by sliding it, the acrylic piece comes off.  Why is this?  I looked for a hidden switch or something but I couldn't find any.  While this is a good idea, this is the only piece of gear such thing exists.  Anyone have any idea/information on this?
Title: Re: HP5335A why is the led cover removable?
Post by: Dr. Frank on April 24, 2018, 08:34:19 am
Many of the instruments of that era had this removable filter plate, like the 5370A/B, and older ones, but also DMMs, if I remember correctly.
Maybe it is from the time when the display was made of Nixie Tubes and light bulbs for the units tell-tale, so that these could easily be changed when failing.

The filter plate of my 5370B was broken, maybe that was happening so often, due to the size, that they made it easily removable.

If you read the 5370  manual, obviously the  LED seven segment displays, and the indicator LEDs were failing sometimes, and they were assembled in sockets.
Title: Re: HP5335A why is the led cover removable?
Post by: tkamiya on April 24, 2018, 05:40:57 pm
What a thoughtful design!