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HP Forum Archive 01

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HP-9114B Cassette Deck
Message #1 Posted by jeff on 6 May 1999, 6:54 a.m.

Does anyone repair these units? I have recently received one that will not pass the self test and when accessed from the HP-71 returns "LOOP BROKEN". Can anyone help with this?

      
Re: HP-9114B Cassette Deck
Message #2 Posted by Steve on 6 May 1999, 7:24 p.m.,
in response to message #1 by jeff

Some simple tests first

NB these are based on HP41 HPIL experience

Are your cables OK? Try looping them from one connector on the 71 to the other. The 71 shouldn't find the device, but it shouldn't report a broken loop either. (do this with each cable).

This should do a basic test of the 71 and the cables.

If this works, then start to suspect the Cassette drive HPIL interface (which you probably already do anyway :-).

There are a number of things that could have gone wrong. I have some vague details of how HPIL worked, but let someone else with experience help out here (all my stuff works, and if it aint broken...)

      
Re: HP-9114B Cassette Deck
Message #3 Posted by Carlos Murillo on 9 May 1999, 2:04 a.m.,
in response to message #1 by jeff

The 9114 uses a sealed lead-acid cell as the power supply. If the cell is bad (expected in equipment this age), it is possible that the voltage supplied to the 9114 will vary as wildly as the output of an unfiltered rectifier. This will certainly cause the self-test to fail. Open the battery pack, take out the lead-acid cell, apply 6V (watch polarity) at the battery connectors (while having the battery case & connectors inserted into the 9114-- you figure out how to do this) and test the drive again. If it works, the culprit is the sealed lead-acid cell.

            
Re: HP-9114B Cassette Deck
Message #4 Posted by jeff on 9 May 1999, 9:02 a.m.,
in response to message #3 by Carlos Murillo

I tried removing the Lead Acid battery and plugged the unit back in and still the Test light did not go off. Could this Battery also cause the "LOOP BROKEN" message? Does the battery have to be present for the unit to work or can the battery be removed and only use the charger 82059?

                  
Re: HP-9114B Cassette Deck
Message #5 Posted by Steve on 9 May 1999, 9:08 a.m.,
in response to message #4 by jeff

If the unit has a Lead Acid battery then it has high current/power demands. Far higher than could be provided by the charger IMHO.

In addition the battery almost certainly acts to regilate the voltage. Having the charger plugged in without the battery could cause high and fluctuating voltages that could upset the unit (or worse)

                        
Re: HP-9114B Cassette Deck
Message #6 Posted by Karl Hafen on 9 May 1999, 2:22 p.m.,
in response to message #5 by Steve

If you decide you need a battery you can get one from www.digikey.com for $16.36 +frt. This battery will also work in the HP-110


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