asdf_x2
Active Member
For a while now, i've been wanting to try out a Yamaha CA-series integrated. I missed out on a local reasonably priced CA-1010, probably only by few minutes. As a consolation i bought a CA-1000 from german epay for not too much money:
It works but some has been inside doing dodgy stuff.
For example destroying solder pads and lifting few on function board. On left main amp board looks like a probe slip and as a result some charring around TP4.
Following components have been changed by clipping off the ones and soldering new ones to the old legs: TR602, TR603, R622, R630. While i measured R622, it broke off. I will replace all of these.
I'm a bit confused since on the left side main amp's TR602 and 603 has the following text: a725 22G (-> 2sa725?). These are replacements.
And on the right side: 58 a763 WL 4B (-> 2sa763?). These look like they might be original or earlier replacements. At least they are not attached to any old legs.
Service manual lists TR602,603 as "2sa572W-4,5".
On power board TR706 has been replaced with ? (see photo).
Service manual lists it as "2sa572WL 4or5".
Should i replace these all with 2SA992?
Also there are no heat sinks on TR702,704 like i've seen in others' pics of CA-1000. It looks like there's never been any.
Should i add them?
The kind person also has cut off the green/yellow protective earth coming from schuko plug to the chassis. For what reason, i have no idea I will reconnect it.
Filter board has been bypassed by soldering the 3 incoming wires to the outgoing ones. As a result filter switches and muting isn't working. I'll leave this for the time being since i have no use for filters. Muting function i might use, so let's see.
I've ordered new caps, trimmer pots, Class A/B microswitches, relay and new flameproof metal film resistors to replace fusible ones.
Is there some other preventive maintenance that this unit should receive?
Despite all this, the unit sounds quite nice even though it hasn't been recapped yet. Especially Class A with headphones. There's something about it i can't describe except it feels like music comes alive in Class A. I'm so looking forward to hearing it after recap and the rest.
It works but some has been inside doing dodgy stuff.
For example destroying solder pads and lifting few on function board. On left main amp board looks like a probe slip and as a result some charring around TP4.
Following components have been changed by clipping off the ones and soldering new ones to the old legs: TR602, TR603, R622, R630. While i measured R622, it broke off. I will replace all of these.
I'm a bit confused since on the left side main amp's TR602 and 603 has the following text: a725 22G (-> 2sa725?). These are replacements.
And on the right side: 58 a763 WL 4B (-> 2sa763?). These look like they might be original or earlier replacements. At least they are not attached to any old legs.
Service manual lists TR602,603 as "2sa572W-4,5".
On power board TR706 has been replaced with ? (see photo).
Service manual lists it as "2sa572WL 4or5".
Should i replace these all with 2SA992?
Also there are no heat sinks on TR702,704 like i've seen in others' pics of CA-1000. It looks like there's never been any.
Should i add them?
The kind person also has cut off the green/yellow protective earth coming from schuko plug to the chassis. For what reason, i have no idea I will reconnect it.
Filter board has been bypassed by soldering the 3 incoming wires to the outgoing ones. As a result filter switches and muting isn't working. I'll leave this for the time being since i have no use for filters. Muting function i might use, so let's see.
I've ordered new caps, trimmer pots, Class A/B microswitches, relay and new flameproof metal film resistors to replace fusible ones.
Is there some other preventive maintenance that this unit should receive?
Despite all this, the unit sounds quite nice even though it hasn't been recapped yet. Especially Class A with headphones. There's something about it i can't describe except it feels like music comes alive in Class A. I'm so looking forward to hearing it after recap and the rest.