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Weber 5e3 advice

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  • Dave H
    replied
    There's only 4 ohms difference between the two halves of the OT but a voltage difference of 75V which implies a 6V6 miss match of 75/4 = 18A! Clearly a false reading. Perhaps it's oscillating when you hang the meter probe on one of the 6V6 plates giving the false reading. Try measuring it with the PI tube removed. If you are comfortable using the transformer shunt method try measuring the 6V6 balance that way. It shouldn't oscillate with the OT shorted.

    Leave a comment:


  • atlantimd
    replied
    I have re checked results below:
    6v6s removed
    V4 pin3 to centre tap = 135.2 ohms
    V3 pin3 to centre tap = 131.2 ohms

    6v6s still removed
    V4 pin3 to GND = 461 V
    V3 pin3 to GND = 461 V

    Tubes in
    V3 pin3 to GND = 337V
    V4 pin3 to GND = 262V

    swapped out JJ in V4 for weber electron 6v6GT
    V4 pin3 to GND = 262V

    I re flowed solder on V4 pin 3 same results

    Is it safe to go ahead using this amp or will damage occur
    thanks

    Leave a comment:


  • atlantimd
    replied
    Originally posted by Dave H View Post
    Welcome to the forum.

    That definitely doesn't look right. V4 has the screen 35V above the plate. I don't know how a 5E3 could be like that. Are you sure those voltages are correct? I wouldn't expect the voltage difference between the plates of V3 and V4 to be more than 5V to 10V max and you have 70V!
    Thanks yes I see this. I am going to re flow solder joints and recheck and will post results here

    Leave a comment:


  • Dave H
    replied
    Originally posted by atlantimd View Post
    V3
    Pin3 to GND = 335V
    Pin4 to GND = 300V
    Pin8 to GND = 19
    V4
    Pin3 to GND = 265V
    Pin4 to GND = 300V
    Pin8 to GND = 19

    Is this a serious problem that could cause a failure.
    Welcome to the forum.

    That definitely doesn't look right. V4 has the screen 35V above the plate. I don't know how a 5E3 could be like that. Are you sure those voltages are correct? I wouldn't expect the voltage difference between the plates of V3 and V4 to be more than 5V to 10V max and you have 70V!

    Leave a comment:


  • atlantimd
    started a topic Weber 5e3 advice

    Weber 5e3 advice

    Hi
    I am new to this forum and this is my first post. I have read a lot of posts and it has been very helpful. My issue which i have been posting on the weber forum started with flickering pilot light which took out the weber power transformer on my 5e3 build. I have replaced this with an EU voltage power transformer from a company called trans amp http://www.trans-amp.co.uk/datasheet...xe%20mains.pdf
    I have eliminated the weber pilot light with the LED mod. All seems to be working well. I powered up with light bulb limiter initialy and its now on its own power. I have installed a new matched pair of JJ 6v6s and new 12a7 jj (V1) and 12axy EH (V2). i tested the voltages and i am getting a mismatch between pin 3 and ground on 6v6 between v4 and v3. V4 pin 3 265volts and V3 pin 3 335volts. See below:

    Copper cap is WY3GT.
    V1 (12ay7) JJ.
    Pin1 to GND = 117V
    Pin6 to GND = 122V

    V2 (12ax7) EH.
    Pin1 to GND = 145V
    Pin6 to GND = 175V

    V3
    Pin3 to GND = 335V
    Pin4 to GND = 300V
    Pin8 to GND = 19
    V4
    Pin3 to GND = 265V
    Pin4 to GND = 300V
    Pin8 to GND = 19

    Is this a serious problem that could cause a failure. I have tried it out and it sounds great more headroom with the new 12ay7
    Any advice would be great thanks
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