This is my first build, the filaments for the tubes are light up but the pilot light is not on and i have no sound. Where do I start ? I have a DMV but I don't know about this kind of troubleshooting.
Make sure a speaker is attached properly! Any hiss or hum at all?
For the pilot light, measure for AC across its terminals. Should be 6.3vAC. (Maybe the bulb is burned out.)
Next, check all your voltages. B+ should be around 400vDC. Make a chart of tube positions (V1a, V1b, etc.) and record DC voltages for each anode and cathode.
If all the voltages check out, then it's time to check the signal path.
I'm going fast. Let me know if you need more detailed instructions![/QUOTE
How do I check my B+ with a meter?
Check you work. Match every wire and connection against the schematic, open by one. As you do, take a pencil and make a checkmark on the schematic at each confirmed connection and component. There are just too many possibilities to give an answer from you post but if you take your time you'll find it.
Very carefully.How do I check my B+ with a meter?
Thanks for help so far. Good news I think I just have a bad bulb because I have 6.3v but my b+ is at 483 volts I am using 5a4c that still seems high can anyone confirmVery carefully.
There are a few different voltages you might typically check in an amp - one is the voltage drop across a component, another might be the voltage across transformer secondaries, and still another, the one being referred to here, is the voltage from a node in a circuit (e.g. B+ at the positive terminal of the reservoir cap) as measured to 0V ground.
When you're checking something like B+ voltage, which is DC, you put your meter on its highest DC voltage range, use an alligator clip attachment or jumper to clip the black probe to a secure ground point, e.g. on the chassis assuming it's properly grounded; and very carefully, not touching anything you shouldn't, place the point of the red probe on whatever node it is you're checking.
I assume you've gotten the obligatory lectures on safety? If you've never checked live high voltage points before, some things to think about: only use one hand & keep the other hand "in your pocket" (famous rule); make sure the meter is where you can see it easily & the probe leads are long enough so they won't pull it over; if the black lead's alligator clip to ground is not absolutely secure, tape it down so it doesn't slip - you don't want to short anything out accidentally; don't have a cat or dog or child in the room to disturb you; remember to unplug the amp & drain the filter caps afterward; etc.
It just makes me nervous when someone says "how do I check my B+ with a meter." It's good to think about how you are going to handle this before you actually do it for the first time. For a full list of suggested safety precautions, p. 189 of this PDF book on solid state amplifiers has an excellent summary.
This is from the triode website.The 40-18016(120V) & 40-18017(120/240V) have a lower HV winding at 660V CT, increased current capability on all windings, which allows you to use different rectifier tube types, add additional tube stages, or upgrade your amplifier to use 6L6's! I would say that is a specifiicastionActually trannys aren't speced for specific rectifiers. Other than the filiment current if it's 2 amps you don't want to use a 5u4 but most aftermarket PTs have 3 amp rectifier filiment windings.
Also keep in mind not all rectifiers put out the same voltage even though they're the same type. For instance I had a JJ 5y3 that put out way more voltage than whatever old USA 5y3 I tried that day.