Goldscan Pulse IV

GD,

Great meeting you the other day and thanks for your kind tips.  I have been listening to the "Treasure Corner" mp3s in my car!  One thing I picked up that is helpful here the probe is probably a good addition to this circuit as Dan recommended to also carry a locator as a separate item and this replaces that.

Excellent idea to separate the power stage.  This could be built into the "battery pack" to isolate it.  The main board could be powered by this or by separate batteries as Foxyrick suggested.  I am thinking of using rechargeable lithiums.  Unless someone already has one of these built to test I think the priority from here is to get one of these built as a prototype as it exists so that the existing design can be benchmarked and we can then look at meaningful improvements to the design so we aren't just tinkering for tinkering's sake.

I have been working on the parts list for Foxyrick.  Does anyone have access to PCB making facilities?


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chudster;

1st, congrats on your 15th.

2nd: I think you have some misconceptions, especially about the 47 ohm resistors, which should have a bypass cap, in the IC side, this is to prevent noise from escaping the IC as much as it is to prevent it from leaking in.... they are an evil necessity.

I am not familiar with the 5534 op amp, (sounds ancient,) I have to look it up, but the LF353, a dual op amp, has jfet input and is designed for high impulse environments. If the 5534 is dual, but I guess its quad, then LF353 is the best, use two IC's for one 5534. The TL064 and -74 are older versions of TL084. I have had poor results with TL081, so I would be wary of any TLn IC. They like dual power supplies. If you are building from scratch, subbing LF353 is do-able.

I have not been following that closely so I went back through the topic:

3R5 is 3 1/2 ohms and if there is a k as in 3R5k, it is 3.5k.... UK convention, I believe;

If this is a PI, dont worry about low noise IC's, use LM324 for the quad op amp, or 2 LF353, as both were designed for single rail;

the RC hobbyists use high current lithium batteries, which are also FAST charging, the common one being 11.1 volts, another is 7.4v or about that. I have been touting the lithiums since I joined the forum (sing the song of li thi um.) ; 

I have been led to understand that the pulse is 5 usec, not 10, if you are blocking the Tx pulse, from the 'receive,' yes, up to 10 usec, or more, and it should be variable, from 5 usec to 10 or 15 usec. Use one  5.1 volt  zener, across the receive input , for prevention of anything over 5.1 v.... what ever supply voltage and definitely for TTL;

personally, I would use two 7.4 v lithium for 14.8 volts and only directly to the high current 'final' transistor, then regulate this down to 12 v for everything else and use all CMOS IC's.... the TTL are limited to 5 volts.

Darn, I said I was going to stay out of this discussion!

Anything else?? Overbuild it and they will come! 

goldigger



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		Quote:			Posted by hesamavr
	No answer ?

The person who designed it knows the answer and they're not necessarily on this forum. Did you think the people here discussing this with you were the designers?

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what is mean 1R(R17) and why in tc4538(D) pin 1, 2 connected to pin 15, 14 .

in the goldscan circuit map give me test points voltag .

what is mean **choke 473 K**?
 

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thank you Eugene

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