26H choke good enough for a grid or anode choke?

speakerfritz · 2nd December 2011, 04:38 AM

I have a 4 watt SE amp that uses a single EL84 tube per channel driven by a single 12AT7. I beefed up the power supply (SS rectified) by adding 4 120uf caps and was happy with the results. I have quite a few 26H miniature chokes and was thinking of trying them out as either gride or anode chokes or both. Is this inductance to low? Should I use a resister in series with it if the inductance is too low? Their size is about 1"X1"X1" .

GloBug · 2nd December 2011, 04:54 AM

26 microhenrys?

Wavebourn · 2nd December 2011, 05:14 AM

26H is good inductance, but I am afraid that your miniature chokes would saturate in such conditions. Most probably they are good for some kind of low signal crossovers, or equalizers. I have tiny transformers, something like 1"x1"1/4", with couple of 12H coils, and they are great when used to equalize RIAA curves for phono stages.

speakerfritz · 2nd December 2011, 01:23 PM

Quote:

Originally Posted by Wavebourn

26H is good inductance, but I am afraid that your miniature chokes would saturate in such conditions. Most probably they are good for some kind of low signal crossovers, or equalizers. I have tiny transformers, something like 1"x1"1/4", with couple of 12H coils, and they are great when used to equalize RIAA curves for phono stages.

Thanks for the reply. The coils were originally PCB mount 120V to 12V step down transformers. A low wattage one, maybe a few VA's. The primary side is 26H's, the secondary side 150mh. So next steps probally should be to figure out what there current rating is.

speakerfritz · 2nd December 2011, 01:24 PM

Quote:

Originally Posted by GloBug

26 microhenrys?

They are 26 Henry's

speakerfritz · 2nd December 2011, 05:39 PM

The second picture looks like an easy install. It looks like at that point in the circut, current shunting would be very low.

speakerfritz · 2nd December 2011, 05:46 PM

The second picture looks like an easy install. It looks like at that point in the circut, current shunting would be very low.

pieter t · 2nd December 2011, 06:05 PM

I would not consider 26H enough for a grid choke.
26H is a little over 3k AC impedance at 20Hz; that will load the preceding stage too much.
The LL1670 in the picture is 540H and that is for a good reason.

2nd December 2011, 04:38 AM	#1
speakerfritz diyAudio Member Join Date: Jul 2008	26H choke good enough for a grid or anode choke? I have a 4 watt SE amp that uses a single EL84 tube per channel driven by a single 12AT7. I beefed up the power supply (SS rectified) by adding 4 120uf caps and was happy with the results. I have quite a few 26H miniature chokes and was thinking of trying them out as either gride or anode chokes or both. Is this inductance to low? Should I use a resister in series with it if the inductance is too low? Their size is about 1"X1"X1" .

2nd December 2011, 05:14 AM	#3
Wavebourn diyAudio Member Join Date: Sep 2006 Location: Pleasant Hill, CA	26H is good inductance, but I am afraid that your miniature chokes would saturate in such conditions. Most probably they are good for some kind of low signal crossovers, or equalizers. I have tiny transformers, something like 1"x1"1/4", with couple of 12H coils, and they are great when used to equalize RIAA curves for phono stages. __________________ The devil is not so terrible as his mathematical model! Wavebourn: We Create Creativity!

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
6C45P Anode choke or resistor?	Peter K	Tubes / Valves	37	27th September 2011 02:21 AM
Issues with grid choke	phrarod	Tubes / Valves	15	23rd August 2009 02:19 PM
Grid choke as I/V?	dsavitsk	Tubes / Valves	1	8th April 2008 06:44 PM
change to grid choke?	Joel	Tubes / Valves	2	5th December 2002 03:20 PM
Anode choke question	tõnu	Tubes / Valves	11	29th April 2002 08:56 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

2nd December 2011, 04:54 AM	#2
GloBug Banned Join Date: Jun 2011	26 microhenrys?

2nd December 2011, 05:46 PM	#7
speakerfritz diyAudio Member Join Date: Jul 2008	The second picture looks like an easy install. It looks like at that point in the circut, current shunting would be very low.

2nd December 2011, 06:05 PM	#8
pieter t diyAudio Member Join Date: Apr 2009	I would not consider 26H enough for a grid choke. 26H is a little over 3k AC impedance at 20Hz; that will load the preceding stage too much. The LL1670 in the picture is 540H and that is for a good reason.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)