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Icepick
Member
Username: Icepick

Post Number: 52
Registered: 1-2002
Posted on Thursday, August 19, 2004 - 11:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

My 138 (old version) has great sideband but when you key up on am, the meter swings up to full scale and then falls back down to nothing. Can anyone give me an idea of what to check out first? Thanks, icepick
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Tech548
Moderator
Username: Tech548

Post Number: 250
Registered: 5-2004


Posted on Thursday, August 19, 2004 - 11:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Icepick

The A/M regulator 2SC-1419 may possibly be faulty. Unsolder it and replace it with a GE-66, ECG-152 or a NTE-152. These are relatively inexpensive. Come to think of it, if I remember correctly, there were more than one of them in there.

If this doesn't remedy the problem, then we'll have to think of something else but the regulator upgrade is a plus anyways.

By the way, is this the 23 channel version or the 138-XLR? By todays standards, both are considered (as you stated) "Old Versions". Either way, we're going back a few years.

Jeff
Tech548
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Icepick
Member
Username: Icepick

Post Number: 53
Registered: 1-2002
Posted on Friday, August 20, 2004 - 11:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thank you Jeff. Unfortunatly my parts list shows only: TR 1,2,4,6,7,8,10,11,12,13,14,17 as 2SC839f/2SC372(0)
TR9,15,16,18,1926 as 2SC945R/2SC372(Y)
TR 23,24 2SC1096(L)
TR 21 2SC1306
TR 20 2SVC1307
TR 3 2SA733H
TR 25 2SC735y
TR 222SC1047D/2sc710c
FET-1 2SK30GR
FET-2 2SK30GR/2SK19gr
Can not find a 2SC1419 in the list.
A different model maybe ??
Thanks .... Urmas

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