I have owned a Fender Hot Rod Deluxe 40W tube amp for about 9 years now, and I believe some of the tubes are on their way out. The problem is the sound is distorted and not being amplified at all, regardless of what position the volume knob is in (I can still hear my guitar output, but faintly).
This amp contains 8 tubes all together, 6 low-level (12AX7) and 2 high power (6L6). According to a schematic I found, all the tubes have test points with expected values for certain conditions (Note 4 in the schematic). So instead of my original thought to buy all new tubes, is measuring these test points a good indication of which tubes may have gone out? Do the high power tubes typically fail first? Seems like I need to be careful with measuring the output of the high power tubes. Anyone have any other suggestions?
The link for a schematic is here:
http://www.blueguitar.org/new/schem/fender/hotrod_deluxe.pdf
(I didn't want to post the schematic here, I am not sure what the forum rules are for posting possible copyrighted schematics)
Thanks.
This amp contains 8 tubes all together, 6 low-level (12AX7) and 2 high power (6L6). According to a schematic I found, all the tubes have test points with expected values for certain conditions (Note 4 in the schematic). So instead of my original thought to buy all new tubes, is measuring these test points a good indication of which tubes may have gone out? Do the high power tubes typically fail first? Seems like I need to be careful with measuring the output of the high power tubes. Anyone have any other suggestions?
The link for a schematic is here:
http://www.blueguitar.org/new/schem/fender/hotrod_deluxe.pdf
(I didn't want to post the schematic here, I am not sure what the forum rules are for posting possible copyrighted schematics)
Thanks.
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