What's the proper procedure for powering up an amp for the first time? Specifically testing voltages before sending it to the tubes.
The power filter section would be my first guess,
but how do you put a load on it before you send power to the tubes?
A Few years back I built a dim bulb tester with GFCI for my first build that worked great.I'm assuming it worked btw (it probably kept me alive) after that I never checked any voltages.
(high V? who cares?shitty soldering it'll hold.)
The power filter section would be my first guess,
but how do you put a load on it before you send power to the tubes?
A Few years back I built a dim bulb tester with GFCI for my first build that worked great.I'm assuming it worked btw (it probably kept me alive) after that I never checked any voltages.
(high V? who cares?shitty soldering it'll hold.)
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Disconnect both channels fro the PSU
Test PSU, with Dim Bulb if you have it, make sure voltages are what you expect.
Attach one channel, test with bulb, if seems good then adjust that channel without the dim bulb.
Disconnect the first channel.
Repeat with the other channel (bulb first, then no bulb and adjust)
If both channels seem good, then attach both and enjoy.
Test PSU, with Dim Bulb if you have it, make sure voltages are what you expect.
Attach one channel, test with bulb, if seems good then adjust that channel without the dim bulb.
Disconnect the first channel.
Repeat with the other channel (bulb first, then no bulb and adjust)
If both channels seem good, then attach both and enjoy.
How do you do that when it's a 2 channel single ended triode? I'm using older power trafos with really old blueprints in a different design. Don't both channels consume an equal amount of power wither there is signal or not.? By adjust do you mean bias?
Sorry it's a new lingo for me lol
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I'm using this original power trafo and tube compliment. Beyond that it's a different circuit that I'm working on.
I'm designing the power filter circuit on diylayout and it occured to me that I'm using a pt out of spec so I'd like to check the voltages of the power filter section before sending it to the individual channels.
290v @100mah in the original circuit.
I'm designing the power filter circuit on diylayout and it occured to me that I'm using a pt out of spec so I'd like to check the voltages of the power filter section before sending it to the individual channels.
290v @100mah in the original circuit.
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Triple check the wiring and grounds first. Put in the tubes but not the rectifier and power up to see if all the filaments light up. Pull the tubes and put the rectifier in and power up to check the voltages, they will be high due to no load so make sure your ps caps can handle higher voltages. Put either a dummy load on the outputs or a sacrificial pair of speakers. Put in one channels tubes and check voltages. If good put the second channel in and measure voltages. If good time for sound! Try a source at low low volume and go from there. Let it run to check for run aways and overheating. Make sure you have a fuse before the power transformer. Remember it can kill you so be cautious and deliberate. Most importantly, have fun!
For first uncontrolled power on (ie after controlled tests) i like to be an extended power cord distance away from the unit (with dummy loads attached) so if any surprises appear I can pull the power cord without being close to the amp.
The first thing i do before plugging in for tests is check the earth grounds to the earth pin of the plug (UK plugs have live, neutral and earth pins). The. Check live and neutral pins, then check for shorts to earth with a DMM.
The first thing i do before plugging in for tests is check the earth grounds to the earth pin of the plug (UK plugs have live, neutral and earth pins). The. Check live and neutral pins, then check for shorts to earth with a DMM.
