Whites Surf PI schematic

[paku]

how about analog meter

[Qiaozhi]

this surfmaster can connect with VDI or not

The VDI circuit will only work with a VLF detector, as it relies on the input from two samples taken 90 degrees apart. From these readings the phase-angle (and hence the target ID) can be determined. The Surf-PI operates in the time domain, and cannot supply the required information necessary for target ID.

[paku]

this surfmaster can connect with VDI or not

[paku]

can you show me how you do with sample picture it will be clear to me

[daverave]

with my surf pi detector i used two piezo elements in some ear defenders which i used as headphones and really loud volume without need of any transformer...nice sharp audio.

[paku]

ok Thanks davor i will try find that transformer

[Davor]

No problem, seek a transformer like the one in the picture, and measure windings resistance. The winding with lower resistance goes to the speaker, and the other one is connected to your machine instead of a speaker. In effect you get a speaker of a larger impedance, and because it is driven with current, it will be louder.
Alternatively you can seek a 50ohm loudspeaker and use it without a transformer.

[paku]

You can use a transformer from an old transistor receiver, and make sure to connect a speaker to a low impedance end. Works for me in another project.

can you show me some sample of picture

[Davor]

You can use a transformer from an old transistor receiver, and make sure to connect a speaker to a low impedance end. Works for me in another project.

[paku]

how to make sound loud with this board

[paku]

hello paku
well done

mix clear laquer or paint (acrylic or epoxi base) with graphit powder and use this as shield

if you dont want to by clear paint
use acetone mix this with styrofoam ( search Q-dope) and add graghit powder (you can measure resistor with meter around 200K setting)

allright thanks bernte_one
Best Regards, Paku

[bernte_one]

hello paku
well done

mix clear laquer or paint (acrylic or epoxi base) with graphit powder and use this as shield

if you dont want to by clear paint
use acetone mix this with styrofoam ( search Q-dope) and add graghit powder (you can measure resistor with meter around 200K setting)

[paku]

i have finish make spiral coil how to shiled this coil any one know

[daverave]

i guess you can as long that you get the transistor pin outs correct

[farafero]

hi

http://www.geotech1.com/forums/attachment.php?attachmentid=27858&d=1389296508

Can I use other transistors instead BC337 and BC 556 ?