Re: KV's and multimeters

To: "'Tesla List'" <tesla-at-poodle.pupman-dot-com>
Subject: Re: KV's and multimeters
From: Tesla List <tesla-at-stic-dot-net>
Date: Sat, 22 Nov 1997 22:10:14 -0600
Approved: tesla-at-stic-dot-net

From: 	Mark S Graalman[SMTP:wb8jkr-at-juno-dot-com]
Sent: 	Saturday, November 22, 1997 7:46 AM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: KV's and multimeters

  I'm  not sure what the circuit layout is, but the beta of the new
transistor may have
been lower resulting in a higher base current being sinked through the
555. Maybe
using the 555 to drive a darlington configuration would take care of that
IF that's
the problem.

                                                              Mark 
Graalman


On Fri, 21 Nov 1997 22:34:33 -0600 Tesla List <tesla-at-pupman-dot-com> writes:
>
>From: 	MATTHEW A PRICE[SMTP:ch038map-at-mode.lanl.k12.nm.us]
>Sent: 	Friday, November 21, 1997 1:45 PM
>To: 	Tesla List
>Subject: 	RE: KV's and multimeters
>
>
>>
>> >From: 	MATTHEW A PRICE[SMTP:ch038map-at-mode.lanl.k12.nm.us]
>> >Sent: 	Wednesday, November 19, 1997 10:47 AM
>> >To: 	Tesla List
>> >Subject: 	KV's and multimeters
>> >
>> >	
>> >Last night I finished the driver for the ignition coil useing a 555 
>timer.
>> >I was surprised when I hooked the thing up and it actually worked!
>........voltage its putting out? My multimeter is a cheapie that only
>goes up to
>> >1000 V. Also why does it spark to everything..even when its not 
>grounded?
>> >
>> >Matthew
>> >
>> >If you want to make better sparks, put in a variable resistor in 
>the
>> 555 circuit. Tune it until you get the longest spark. The best 
>ignition
>> coils are the red or blue ones. These are specially for use w/ 
>transistors.
>> Also, TV transistors arent the best. IGBTs are the best, but simply 
>a 3055
>> is ok. My ignition coil throws 3/4 inch sparks easily. Or, if you 
>want to
>> make the longest and fattest sparks, use a thyristor in series with 
>a 1uf
>> cap and the primary. Feed this arrangement with 250 VDC. The cap 
>charges up
>> and discharges throught the primary. I used 350 VDC and a 4,7uf cap, 
>that
>> made 2 1/4 inch sparks!
>> Atle Jorstad
>
>Help!!!! The driver that I was talking about is now giving me seriuos
>problems. I replaced the TV transistor with a 3055 and the voltage 
>was, as
>you said, increased, but the thing quit working. After trying a few 
>things
>I decided to try a new 555, and it worked again, but quit again. I 
>decided
>not to fry anymore 555 (thats what I was doing, and the things don't 
>grow
>on trees!) so I wanted to ask you guys what I am doing wrong. Part of 
>the
>problem may be that I need a higher voltage rated wire, but I don't 
>know.
>The second time it only ran for a few seconds, and I didn't touch
>anything... Please tell me what I am doing wrong
>
>Thanks
>Matthew
>
>
>
>