Beta Matching and Multi-Coil Machines

[Joster]

Hi All,

I am saving up to buy a bunch of MJL's to do Beta Matching. Just wondering if anyone out there has had experience running the SG before and after Beta Matching. How did it effect the charging rate?

Also, I'm wondering on machines like the 10-coiler, are all those MJL's Beta matched? Or are they Beta matched for each individual coil?

Cheers!

[Tom C]

you should always match transistors for each coil you run, even better would be to match them for all coils, this was not done with the 10 coil units, it should have been. the reason you match the gain is so all the Bases open the same amount.Tom C

[John_Koorn]

Hi All,

I am saving up to buy a bunch of MJL's to do Beta Matching. Just wondering if anyone out there has had experience running the SG before and after Beta Matching. How did it effect the charging rate?

Also, I'm wondering on machines like the 10-coiler, are all those MJL's Beta matched? Or are they Beta matched for each individual coil?

Cheers!

Joster, my tests showed about a 10 percent increase in performance when the transistors were matched.

John K.

[Faraday88]

Hi Tom C,
How does one ensure that you get the same Beta for all the Transistor you buy..? one method is to buy them in quantity, and then 95 % of the transistor belonging to the same Manufacturing batch will have the close match... your comments please..
Rgds,
Faraday88.

[Tom C]

we buy large quantities and beta match them here that is the only way I know of.................. Tom C

[John_Koorn]

... 95 percent of the transistor belonging to the same Manufacturing batch will have the close match...
Rgds,
Faraday88.

You'd be surprised at the difference even in the same batch Even with reputable manufacturers.... all made in China

John K.

[Faraday88]

Hi Tom C ,

I remember John Bedini saying that they (with Peter) had to buy 100's of them to get the right match of Beta in all the transistor...
rgds,
Faraday88.

[Tom C]

Transistor matching comes from amplifier design, large wattage MULTI DEVICE amps are always matched to put them into class A mode, THD .01 all of Johns amps are put into class A before he sells them. when you saw Johns bike wheel kit there were no neons, because the transistors were matched and if the charge battery gets disconnected all the transistors can share the spike and don't blow up (sometimes) if one transistor is different kablooeey!! the neon helps prevent destruction of mismatched transistors AND accidental disconnection. even then its only a momentary protection. a monopole will be more efficient and will charge better if they are matched. the gain in the circuit comes thru the base collector junction..... Deborah chungs negative resistor. Tom C