150 Scope Issue

They didn't touch it, the two screw threads were different, one was a proper machine screw and the other was a longer course thread screw- one was a black screw and one was silver. SUB can verify if this is what he used.


iq49.jpg
 
Is there any reference in the service manual or parts list stating that plastic screws as opposed to metallic screws should be used?
Are the plastic screws the clear type?
I do remember seeing plastic screws to hold the horizontal & vertical drive transistors when I replaced the horizontal drive transistor in my Marantz 2130 P900 board.
 
This little detail, as obvious as it seems now, did not occur to me when I was replacing the screws. :(
 
Well-done, BK, you are truly 'The King!' :ntwrthy::ntwrthy::ntwrthy:

And thus ends one of the longest troubleshooting threads in AK history!!!
 
This little detail, as obvious as it seems now, did not occur to me when I was replacing the screws. :(

When I worked on my 2130 with a similar problem, I replaced the screws with the screws (plastic) I removed, never thinking outside the box.
Sub, you learned something for future repairs.
Great patience BK & Petehall347
 
Well-done, BK, you are truly 'The King!' :ntwrthy::ntwrthy::ntwrthy:

And thus ends one of the longest troubleshooting threads in AK history!!!

I think I have two of the longest troubleshooting threads. Chck out my 2238b thread. Bk and Pete solved that one too.
 
I got my 150 back today from BK safe and sound!

I think I may have thrown something off when I was messing with the Gain and Vert / Horiz pots (R915 and R916) because the 2 channel output seems slightly off. It doesn't look symmetrical on the bottom and top half like it used to and the dot seems to move in a curved fashion with audio instead of a linear. Here is an example:

1zrj.png


Should I follow section 8 of the service manual? I think I may need to adjust the vertical / horizontal pots R915 and R916. See section 8 of the service manual. Though I'm not sure how to "feed in 130mV to the 'scope inputs, front R' jack and adjust R915 (HORIZ) to obtain a horizontal deflection of about 4cm."
 
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I got my 150 back today from BK safe and sound!

I think I may have thrown something off when I was messing with the Gain and Vert / Horiz pots (R915 and R916) because the 2 channel output seems slightly off. It doesn't look symmetrical on the bottom and top half like it used to and the dot seems to move in a curved fashion with audio instead of a linear. Here is an example:

1zrj.png


Should I follow section 8 of the service manual? I think I may need to adjust the vertical / horizontal pots R915 and R916. See section 8 of the service manual. Though I'm not sure how to "feed in 130mV to the 'scope inputs, front R' jack and adjust R915 (HORIZ) to obtain a horizontal deflection of about 4cm."

To adjust the Horizontal & Vertical for the scope display you need a function generator with variable output (with a wide range so you can make adjustments in small increments) and an accurate DMM that can measure ac mV
 
I played around with the horizontal and vertical gain (R915 R916) and that helped a little, but there is still some curve to the output.

Are you saying I need a function generator to be able to feed the 130mV to the scope inputs? Do you think this will fix the problem, even though playing with R915 and R916 didn't fix it?
 
How does it look on FM vs 2ch. I didn't test 2 channel EXT as I mentioned in my pm-have you tried cleaning the switch itself with some deox?
 
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