Sir fred3 . . . . .
blowing an exploratory $80.00 + pig-in-a-poke ?
(Plus there is a CHEAPER alternative for that isolation transformer if . . .IF . . . IF
initially troubleshoot . . .thusly . . . . .
CHECK YOUR UNIT FOR THESE COMPARATIVE ASPECTS . . . . .
Item 1's of which, one may be the diamond shaped TO-3 encased 3 terminal regulator
and its like shaped heat sink. And this photo seems to suggest of a TO-220 shaped 3 terminal plastic 3 terminal regulator and its rectangular shaped companion heat sink .
item 2's blue cased AXIAL main electroltytic capacitor.
Examine the markings on all items . . . . . of particular interest will be a 7812 or 7815 on the far left regulator and possibly a 7805 on the right regulator.
The item 2 will have a capacitance and DC working voltage identification.
Also look at the right top corner for the 2 companion RADIAL leaded E-capacitors for their voltage rating and capacitances.
Move down to the Photo 4 and see the possible alternate use of a second TO-3 ( BOTH RED
CIRCLED)and thus, the vacancy of the second previously pointed out plastic TO-220 at the top.
Look to bottom right corner and get that 3 terminal plastic TO-220 numbering and also the 4 o clock positioned RADIAL E- cap's voltage and capacitances..
MOVE TO PHOTO 2 . . . . .
See if they used / incorporated either phone line and or power line suppressors . . .within 10 ft of your unit.
The ferrite filter blocks shown down at the bottom mainly have to do with any STRONG nearby AM radio station coming in on the background.
Look at my Photo 1 GREEN SQUARE of the unit ground wire to case and then to Photo 3 and its connection into terminal block #3.
MAKEE -MAKEE- TESTEE- TESTEE
Get your unit making its nasty noise and take the ground wire loose from board terminal 3.
Does the problem change ? then listen while you put it back into connection with terminal 3. . . . . . any change ?
If satisfied, of no problem, reconnect to #3 and tighten along with its other ends terminal and its screw, along with its biting in lock washer . . . . . . to be TIGHTENED.
Initially, take note or mark each of the incoming phone wires on terms 1 and 2 and then remove to see if the offending noise still is present ? ? ?
If so, we are then suspect of the 1830 board, so that is why the collecting of the data on the regulators and their related E caps .
. . . . . . . now talk some technicalese to me . . . . . babe . . . . .
MAGNIFICENT TECHNO PHOTOGRAPHIC REFERENCING . . . . .
(also Hosted) at
(Or the WHOLE fuchbuk is @
73's de Edd . . . . .
Conserve Toilet Paper ! . . . wipe with both sides of the sheet.