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Tantal Cap - strange color code?
05-01-2018, 08:45 AM (This post was last modified: 05-01-2018 10:33 AM by AndiGer.)
Post: #1
Tantal Cap - strange color code?
There is a - I suppose - tantal capacitor inside my HP-97 main baord with strange color code that has to be replaced.
   

Orange head, pink - red - green lines. No colored dot but blue line to indicate anode I guess.

According to the service manual could be C1 (2.2 µF) as it's anode is attached to T1 inductor and cathode to 2 diodes - CR6 and CR7?
C3 located near ACT / PIK has the same strange color coding.
Not cleary visible in the lower part of the picture you can see yellow - purple (C6?) cap (orange marked head, brown or grey dot) and red - red - black dot (C4?) cap.

The board's layout isn't the one given in the service manual - all 5 ROM chips in a line. So the position of the other components is also different.

Anybody suggest a replacement? Is it 2.2 µF? Thank for your advice / experience.

Edit: added . in C1 2.2uF
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05-01-2018, 10:27 AM
Post: #2
RE: Tantal Cap - strange color code?
(05-01-2018 08:45 AM)AndiGer Wrote:  There is a - I suppose - tantal capacitor inside my HP-97 main baord with strange color code that has to be replaced.


Orange head, pink - red - green lines. No colored dot but blue line to indicate anode I guess.

According to the service manual could be C1 (22 µF) as it's anode is attached to T1 inductor and cathode to 2 diodes - CR6 and CR7?
C3 located near ACT / PIK has the same strange color coding.
Not cleary visible in the lower part of the picture you can see yellow - purple (C6?) cap (orange marked head, brown or grey dot) and red - red - black dot (C4?) cap.

The board's layout isn't the one given in the service manual - all 5 ROM chips in a line. So the position of the other components is also different.

Anybody suggest a replacement? Is it 2.2 µF? Thank for your advice / experience.

C1 is marked as 2.2uF in the manual I have and matches the position in the circuit as you described with (+) connected to the inductor.

cheers

Tony
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