Is it necessary to reset BIAS after Re-Capping Power Suuply (MC 2205)

[MC2205]

Hey guys! I just recapped my power supply on the Mc2205 using The colonels kit on ebay. However im reading online , I may need to re adjust the Bias now. Im not equipped to do so at home. Can anyone share some information ? Thank you kindly.

 

[jlovda]

Buy a "Kill-A-Watt" 4400 home energy monitor on Amazon and you will have all the test equipment you need to adjust the bias.

https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU/ref=sr_1_1?crid=28RF5BI0PD0FO&dib=eyJ2IjoiMSJ9.frevdwDrQpXCgm3d6NT81GxTyIfbiTUu3MoX2zwvcqReccan853YS4lg6Of6mzmEL1Zjul7pRj10awD5q_B2SNKbJkVJ5hQRtKKU8P-bC7gMLzlkU75rA9nkDFdvD3mdZg8sHSSqdhri04w6p_qF4NvnrcZLdUxMlHBtK2_U1hvT1Z8Njye3djnAkRPCzyw07ImQf8Kgu3jrMphtBajfaOy6esTHR-KId827rKGIaJji6_rwjh8PZC-iEYUEaRXCLVEyL-gdsYWVQ-ytoC_uc2rAVYzvURaxrTkev2AGimc.IUtmc_hOlwGFLHZOcFsXfEEVvfnX4wuPDeKmLNe4pkQ&dib_tag=se&keywords=kill-a-watt%2Bp4400&qid=1769782655&sprefix=kill-a-watt%2Caps%2C148&sr=8-1&th=1

 

[gadget73]

I'd certainly want to verify it is set correctly after making any sort of changes. Or just from age, parts drift and its worth checking every few decades.

Whats the official procedure, adjust for some current draw from the wall, or is it a measure across an emitter resistor like most things?

 

[w3jn]

As mentioned above, use a Kill-a-Watt or VOM in AC current mode, in series with the line plug.

 

[Jose Jimenez]

Hey guys! I just recapped my power supply on the Mc2205 using The colonels kit on ebay. However im reading online , I may need to re adjust the Bias now. Im not equipped to do so at home. Can anyone share some information ? Thank you kindly.

I have two of these amplifiers since new. In the manner explained above, the bias circuit does its best to track the output in an "energy conserving" Class B configuration. I turn them on with the pots turned down and slowly increase them until the heat sinks remain at a comfortable 82 degrees F in a room approximately at 70-72 degrees and no drafts. These amplifiers have been upgraded with MJ21193/94 output devices last year and all is copacetic. You may still want to sneak in an Ammeter in circuit to get an idea where the amplifiers start to conduct drawing current when turning the potentiometers up when adjusting the bias to save some time. I'm in no hurry.