Newly finished amp based on a Z-28 but using 5881 tubes...
Sine wave shows up at speaker jack (8 ohm load or 8 ohm speaker attached) but no audio signal can be heard when speaker is plugged in.
Output transformer reads:
Primary: 411 ohms end to end / 205 ohms CT to each plate
Secondary: 0.5 ohms
Any thoughts, opinions, etc would be much appreciated!
TT
plated voltage = 443v 27mA per tube
New Amp Build, Sine wave at Speaker Output, No sound
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New Amp Build, Sine wave at Speaker Output, No sound
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Re: New Amp Build, Sine wave at Speaker Output, No sound
Cliff Jacks... Stinking Cliff Jacks... I hate Em... Always seem to wire them backwards! 
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Stevem
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Re: New Amp Build, Sine wave at Speaker Output, No sound
That mistake of having a open circuit due to a mis-wired jack can cost you a shorted OT if the amp is played loud enough with that condition.
Get yourself a 250 ohm 5 or better yet 10 watt resistor and wire it across that jack so if your cable you use ever goes open or you blow your speaker(s) your OT will still have a load on it.
$1.50 will save you 80 bucks potentially
Get yourself a 250 ohm 5 or better yet 10 watt resistor and wire it across that jack so if your cable you use ever goes open or you blow your speaker(s) your OT will still have a load on it.
$1.50 will save you 80 bucks potentially
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: New Amp Build, Sine wave at Speaker Output, No sound
Signal at the jack, and no sound means the speaker or cable is bad, or the jack is missing the return (if your scope is using the chassis as a ground.
That square wave indicates an overdriven amp, if it had a sine wave input. Hi power and no load equals disaster.
That square wave indicates an overdriven amp, if it had a sine wave input. Hi power and no load equals disaster.
Tube junkie that aspires to become a tri-state bidirectional buss driver.
Re: New Amp Build, Sine wave at Speaker Output, No sound
This has saved me a lot of trouble. I would like to give credit but no longer remember who gave it to me. It's got a 2007 date stamp.
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