Hi,

I was looking at adding these to my old 3-500Z amplifier or my 811H.  Has anyone here looked at or better yet used them in their amplifer?  Opinions?  

Thank you,
Randy AB9GO


Ameritron GOP-100 Grid Overload Protection board:
http://www.ameritron.com/Product.php?productid=GOP-100

Ameritron EBS-1 Electronic Bias:
http://www.ameritron.com/Product.php?productid=EBS-1H

I checked the website and it is $300 more, not a $1000.

Randy

Maybe this is what they are adding?

http://www.ameritron.com/Product.php?productid=GOP-100

GOP-100 is Grid Overload Protection for all amplifiers.

Thanks, I'll check it out.  Here is a little from the catalog

"NEW!  Get the AL-811HD with 572B tubes... $XXXX

AL-811HD gives you the AL-811H with four 572B tubes installed.  Get a higher power tank circuit and grid overload protection....."

I just noticed this in the MFJ/Ameritron catalog.  Is there a schematic out yet?  There is supposed to be some protection circuits added in adition to using 572B's instead of 811's.  I would like to comnpare it to my 811H and maybe if practical, add the protection circuits to my old amp.

Thanks,
Randy AB9GO

"And the new cheapie QRP version is set to go on sale next month."

Why wait?  Get and build a SoftRock v6.3 now.  QRP and cheap!
http://www.wb5rvz.com/sdr/RXTX_V6_3/

Randy AB9GO

The Hickok 539 used a 5y3 and a 83 mercury vapor rectifier tube.  Turn on the tube tester and power it on for 10 min before testing and see if the unit improves.  Those 83's were problematic if not used for long periods of time.  The mercury condenses on the internal elements and needs to be made a vapor once again.  No copper oxide or selenium rectifiers in that one.

Good luck!

Randy AB9GO

p.s.  I own three Hickoks and I find that they are excellent units, just warm them up if stored for extended periods!

This is a euro external anode triode with a coaxial base.  Are there sockets available for this tube?  I have 3 sealed NOS in the box that I would like to do something with or trade them off for something I can use.

Thank you,
Randy AB9GO

Tube data here:    tubedata.tigahost.com/tubedata/sheets/030/t/TBL2-300.pdf

Toms tubes  www.tomstubes.com?  Is he a SK?

Thank you,
Randy  

p.s.  Ask for Debbie or Tom.

Check with Debco Electronics @ www.debco.com Phone # 01-513-531-4499.  They have some old stock Dentron meters that look like the type in your amp.  The scale was different but the case and cover are the same.  

Randy AB9GO

Thanks.  I'll send you the "C" schematic as soon as I find one.  From what I am finding out the Amp Supply amplifiers were a continual work in progress.  Many have said that the correct exact schematic for many of the LK series simply does not exist.  Modification of the circuits was ongoing and continual.  I'll send you what I can find.

Randy AB9GO  

Hello,  My 500B uses a 120 V single speed fan, but with a resistor in one leg of the AC feed.  You can use a standard fan with this arrangement and get two speeds by putting a switch across the resistor.  The resistor on my schematic is R4 250 ohm @ 10 watts.  You are going to have a hard time finding a two speed fan either surplus or off the shelf @ a supplier as they were not commonly used.  

Question.  Do you have a scanner and if so would you please scan the schematic and parts list of your 500C?
My Email address is randallr@healthall.com

Thank you,
Randy.

A couple of years ago at a yard sale I bought a Pride 300 amp.............

I agree, a better quality amp than most aimed at the see bee'ers out there.  I wish I could find one at a yard sale.  You were lucky indeed.  They still command a higher than normal price on Ebay for a 300 watt amp and I bet that you grinned all the way home if you got it for a yard sale price!

Randy AB9GO

p.s.  I have the QSK model.