For sale bare boards for Delta Pulse/Sniffer XR-71

[kt315]

thank you George for support in this hardest deal. your understanding of the situation is perfect, like always.
really this guy loves to overload me by blank empty requests (he loves to write doubles in PM too).
certainly i am on nerve... my bio-energy stock is long ago in state red LED 'ON'. i have to sound like an elephant long away.
this guy with zero level of a lamer went whole stages to the finish and on every one i said myself just WOW. he got a result - reaction on metal.
that is absolutely rare thing we see here in geotech. THE record. while i still waited the Magic Smoke... on every his step...
that occured. now he asks help... those people set sockets on every chipo... they so love to set the sockets...
but for what ? they do not understand. 'because all people set the sockets and i will do same' - their main principle in their life.

all the best

[kt315]

To put it simply, turning up the depth pot, increases the pulse width of the TX, which increases the "ON" time of the MOSFET. This means that the MOSFET is now going to dissipate more power (heat), which is why you have to put it on a heatsink. Otherwise you can damage the MOSFET.

there is a specific limitation of the voltage amplitude on peak. MOSFET is working like Zener diode if the peak-to-peak
amplitude is above 400V. whole cutted top of the delta pulse, his energy, certainly goes in the heat.
so 100-150us PULSE WIDTH is still within the permissible, 'safe', no the limitation and heatsink is not needed, but on 400us and more we get the excess heat.

[Qiaozhi]

certainly i am on nerve... my bio-energy stock is long ago in state red LED 'ON'. i have to sound like an elephant long away.

Try to stay calm...

[chuubaba]

Kt try to look at things from my side too. Imagine you are a caveman and suddenly you are building a DP. Just try it. Better not sell me another board.

What you think is problem with the board. Both LED are off. No component is heating. There is clicking sound if i touch bottom of the board. I have replaced MOSFET and DA7 but it is not working. Thank you.

[chuubaba]

Now i have replaced all ICs but the board is not working.

[Qiaozhi]

Kt try to look at things from my side too. Imagine you are a caveman and suddenly you are building a DP. Just try it. Better not sell me another board.

What you think is problem with the board. Both LED are off. No component is heating. There is clicking sound if i touch bottom of the board. I have replaced MOSFET and DA7 but it is not working. Thank you.

Now i have replaced all ICs but the board is not working.

Read post #883.

[chuubaba]

Read post #883.

Thanks. What you think is wrong with the board?

[Qiaozhi]

Thanks. What you think is wrong with the board?

I think the problem is that a caveman has been let loose with a soldering iron.

Seriously man ... put it to one side and teach yourself some electronics. You're going to cause KT315's head to explode, and possibly some collateral damage to yourself.

[dbanner]

there is a specific limitation of the voltage amplitude on peak. MOSFET is working like Zener diode if the peak-to-peak
amplitude is above 400V. whole cutted top of the delta pulse, his energy, certainly goes in the heat.
so 100-150us PULSE WIDTH is still within the permissible, 'safe', no the limitation and heatsink is not needed, but on 400us and more we get the excess heat.

Yes. But Chuub does not have a clue of this. So I try to explain using simple language.
It's a goddam miracle he got it to work at all!!!!
That is definitley some kind of record.
I like this guy, he is truly one of a kind.

Chuubaba, you keep going. Just don't burn the house down.
Geotech forum cannnot be held responsible for any insurance claim.

[Andi68]

Check the transistor driving the mosfet

[chuubaba]

Dbanner changing block connectors was the last major event. Do you think the board is damaged during the process?

Admin thank you for your verdict. If i am expert and creator of something then it does not cause my head even a spark to workout anything about it. I wonder how you call yourself a expert and me a novice. You also got no clue so whats difference btw u and i.

[chuubaba]

Check the transistor driving the mosfet

Andi . God sent me an angel. I am going to find and check it immediately.

[dbanner]

Sorry Chuuby, I couldn't resist.

[kt315]

Check the transistor driving the mosfet

longest rip away you send him seeking this transistor. DP mosfet is driving directly from/by NE556.

[chuubaba]

Sorry Chuuby, I couldn't resist.

BTW which transistor drives MOSFET? I want to replace it.