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Re: need help with transformer

PostPosted: Sun May 27, 2012 12:08 am
by tekiding
thank again allen and also thanks sich,

i already halfway to making this device(hopefully it works)...,but still about the transformer...,should i assemble the full circuit to test the transformer or can i test it like the picture i attached previously...only half of the circuit...,

p/s: sich...i wanna build a stimulator.., TENS...

Re: need help with transformer

PostPosted: Sun May 27, 2012 5:39 am
by ABSF
tekiding WROTE:thank again allen and also thanks sich,

i already halfway to making this device(hopefully it works)...,but still about the transformer...,should i assemble the full circuit to test the transformer or can i test it like the picture i attached previously...only half of the circuit...,


Yes, you can test your circuit with the partial circuit you attached OR you can also test it using a simple 555 timer circuit. The timer should be in astable mode generating about 10KHz of square wave driving a small NPN transistor like BC547 or 2SC1518. The 17T coil connected to the collector through a 500 ohm resistor to +9V. You should get some AC voltage on the 44T coil.

Allen

Re: need help with transformer

PostPosted: Mon May 28, 2012 12:22 pm
by tekiding
i got timer ne555 and oso timer 7555... can i get the circuit digram for testing using the timer that u mention?

Re: need help with transformer

PostPosted: Mon May 28, 2012 4:58 pm
by tekiding
this is what ive done so far...the prob is when i turn on the switch..i use DVM on the transformer primary,i use the ac mode i got reading +- 1.7 V to 2.6V (using ac) then i try dc mode i got +- 0.17V to 0235V (using dc) but nothing happen on the secondary.... T..T

Re: need help with transformer

PostPosted: Wed May 30, 2012 2:48 am
by tekiding
i already troubleshoot and check all the connection and component..i make a few mistake...after making correction, i test it using led..then the transformer got input and output which mean the circuit makes the led turn on..but still i cannot measure it with DVM for the transformer... seem like the voltage not stable...im not sure...just wanna share..,
got any suggestion or comment...im open to hear...thanks a lot...especially allen...

Re: need help with transformer

PostPosted: Thu May 31, 2012 1:13 pm
by tekiding
hye...i already finish assemble the circuit...and it function,at the output electrodes it generate a small electric pulse but not as strong as the TENS..im glad that it working...thank you so very many much especially ALLEN. i dont know how to repay except big thank..., :roll:
neway..,if u have any idea or suggestion on how to make the output 'strong'..plez do tell me..,coz i already make the variable resistor to full value n zero value...the strength of the electric shock at the electrode is same..but still im a bit satisfied..,again thank you

Re: need help with transformer

PostPosted: Thu May 31, 2012 6:27 pm
by ABSF
Congratulations that it is working. Hope you enjoy doing the project. I am going away for the school holidays and the Gawai holidays tomorrow, so I wont be around for the whole next week. And BTW

Did you use the sticky pad electrodes that I recommended (Made by OMRON).
What is the battery voltage?
What are the DC voltages after D1, at Pin 8 of 7555 and pin 6 of IC2?

Allen

Re: need help with transformer

PostPosted: Thu May 31, 2012 9:34 pm
by robosang
Allen, Happy Gawai Day!

Re: need help with transformer

PostPosted: Fri Jun 01, 2012 9:48 am
by ABSF
Thanks, but I am not celebrating it or doing any visiting to my Dayak friends. Just making use of the holidays for a vacation. ;)

Allen

Re: need help with transformer

PostPosted: Thu Jun 07, 2012 7:24 pm
by tekiding
happy holiday to0.. :D
ABSF WROTE:Did you use the sticky pad electrodes that I recommended (Made by OMRON).
What is the battery voltage?
What are the DC voltages after D1, at Pin 8 of 7555 and pin 6 of IC2?
Allen

i buy the TENS unit from lelong and modify the stickypad
im using a 9V battery btw can i change the battery to adjustable adaptor?

b4 i could check at pin8(7555) and pin6(IR2153)..,something happen(which i got no clue)..maybe a random error.. :lol: kidding on the random error but right now i got no output at the electrode...,i troubleshoot,recheck the soldering i made but got nothing..the i use led to check voltage when accidently i short cct the connection(at blue circle) to ground and there's output at the electrodes but then i need to tap again and again from this point(blue circle) to ground to get the output at the electrode...so right now im clueless :?:

is it maybe the MTP6N60C(in red circle) that i use instead using MTP6N60E.but the connection is right and the datasheet for this 2 almost the same
MTP6N60E = #6.0A #600V #Rds=1.2ohm
MTP6N60C = #5.5A #600V #Rds=2.0ohm