DIY Audio Projects Forum

DIY Audio Information for Beginners
Page 7 of 7

Author:  Geek [ 04 Mar 2017, 13:38 ]
Post subject:  Re: DIY Audio Information for Beginners

A note for those not in the know - relay datasheets usually warn of contact contamination from off-gassing of the coil when energized for extended periods. Hence use the coil with lowest power consumption (the H1 for Omron for example) for longest life. Don't try and save a few pennies by opting for the regular high power coil.

Like M. Gregg, I've never had one fail.


Author:  Woodo [ 23 Oct 2018, 17:56 ]
Post subject:  Re: DIY Audio Information for Beginners

this site may have been posted elsewhere but thought it worth a mention in this thread. Mr Turners site contains a lot of information which may be of use to someone. credits to Mr Turner for maintaining his site even while he is enduring health concerns.

Author:  M. Gregg [ 27 Oct 2019, 03:35 ]
Post subject:  Re: DIY Audio Information for Beginners

I would like to raise a point,

We are all aware of discharge resistors in power supplies and that its " bad practice" to not have a discharge path ie something like a resistor across the B+/HT charged capacitors. This is of concern linked to children in houses that may push hair clips through ventilation holes or where tubes could get broken when not in use.

So you don't want equipment holding high voltages for extended periods when little Joe or Diane decide to do an experiment just like daddy does and push something into equipment that could be conductive.
Its also an interesting build experiment to see how child safe and pet safe internal you can build. Things like iron circuits behind vent holes or where HT is not accessible from the outside i.e. you need to go at 90 degrees to access it. I did this as an experiment with my EF86/ EL84 build and tried to build enclosed with a tube rectifier.

Its also interesting to note that "Standard tube rectification" uses two B+ windings where the total voltage is across the two ends of the B+ secondary. As opposed to a tube rectifier with a diode return path hybrid rectifier using just one B+ winding half the voltage.

Remembering of course that as you solder on a project that the solder is conductive and you are holding it. :hot:

NB one other obvious point is equipment holding charge when someone tips a drink over it and then gets a cloth to wipe it up before anyone sees it.
You would think off is safe but of course we already now this but others don't. :up:

M. Gregg

Page 7 of 7 All times are UTC - 6 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group