Home
AudioAsylum Trader
Tubes Asylum

Questions about tubes and gear that glows. FAQ

For Sale Ads

FAQ / News / Events

 

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.

You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login


Login to access features only available to registered Asylum Inmates.
    By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username:

The Name that you picked or by default, your email.
Forgot Moniker?

 
 

Examples "Rapper", "Bob W", "joe@aol.com".

Password:    

Forgot Password?

 Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:  
Your Email:  
Subject:  

Message Comments

   

Original Message

RE: That is the electrical equivalent to a 5R4

Posted by Tre' on April 25, 2017 at 17:37:20:

"Which has a 4uF first cap limit"

No it doesn't.

It has a max peak repetitive current rating (like all rectifier tubes) that can not be exceeded.

4uf, depending on the voltage, current and resistances involved, can cause the max peak repetitive current rating to be exceeded while in a different situation with different voltage, current and resistances a 50uf cap would be fine.

I have stated this truth about rectifier tubes and tried to explain about the input cap value given on the data sheets and what it means many times but no one seems to listen.

The data sheet linked below shows a input cap value of 20uf. The data sheet also shows the operating conditions that allows that value.

If you have different operating conditions then the max input cap value will be different.

Again, it's the max peak repetitive current rating that can not be exceeded.

If the voltage is less and/or the current is less and/or the series resistance is more then the uf value of the input cap can be higher without exceeding the max peak repetitive current rating of the tube.

There is no magic "max input cap value" associated with rectifier tubes.

Tre'