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PB 3400c DIY power adapter
Posted by: Crutch on 2019-12-27 11:24:15
I just got a cheap 3400c in unknown condition with no AC adapter. Noticed some enterprising people selling the right adapters for $50 on amazon but .... curious if anyone has had success building a simple DIY version of these. The DC power port on the back of the 3400c fits a standard RCA cable snugly. Any reason I couldn’t just solder up a male RCA connector to any old 12v DC adapter capable of providing 2 amps?

Posted by: Trash80toHP_Mini on 2019-12-27 20:11:45
Aren't they 24V like the Duos and 1400? You need a voltage converter to run 'Books off 12V in a car.

Posted by: Crutch on 2019-12-28 06:37:58
Sorry, yes, 100% correct.  That was a typo.  I meant, is there any reason I can’t just wire up a plain ol’ 24V DC adapter to an RCA male plug ...  (I bought one for $9.99 so am going to try this unless someone tells me I’m crazy...)

Posted by: Trash80toHP_Mini on 2019-12-28 08:46:46
Like the rest of us in the hobby, I'd have to say you are crazy. Also, outside of the joys going all Rube Goldberg on bodging something you could easily snag for $50 NIB for testing a cheap 3400c in unknown condition would be another symptom to consider.

DEGUBBING

For hardware: starting from one known good component and testing for only one variable at a time thereafter. NIB or known good adapter would be my baseline. [😉]

edit: if this one is a goner, bottom feeding all manner of questionable 3400s to build up a spare parts inventory, searching for a MaxMem card at the same time, you can easily test them as well.

Posted by: Crutch on 2019-12-28 08:50:12
Yeah I admit my risk tolerance here is pretty high. Mostly because I only got the 3400c in the first place so I’d have the correct color key caps for my 550c ... also crazy I suppose! 

Posted by: Trash80toHP_Mini on 2019-12-28 11:11:17
Not really, parts is parts! :approve: Surprised they fit. Are any other pre-100 series PB's key caps interchangeable?

Posted by: Crutch on 2019-12-29 10:47:25
Update - this did not work. Whether the PB is bad or my DIY power supply attempt failed somehow remains to be seen, pending arrival of the proper aftermarket power supply I bought for $40. I had fun trying it though. 

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