looking for home-made G.P.R.

[Valchev]

Hi Alexismex,
I do not know why I have not received Yours E-mail. Due to this I make new e-mail, can use too: [email protected]
I receive e-mails from Geotech Forums always, and from а lot of points of the world.

[Valchev]

Hi Mosha,
My GPR is classical.
GPR transmit the short pulse in the ground. When the pulse (radio wave) encounter changes in electrical and magnetic properties(as dielectric permittivity, conductivity) of middle (ground) occur radar reflections . GPR receive reflected pulses. GPR can to show objects with diferent electrical and magnetic properties than the middle (ground). GPR can detect metal, but for good reflections GPR nееd a metal object to be big and flat or long (pipe) . Due to this i think that for treasure hunting GPR is most suitable for a objects as cavities and tunnels ......

[mosha]

hi valchev

is your GPR image only caves?!! what about others material?

[Alexismex]

bad email

Hello Forum ,
I try also to contact Petar3 times with the differents mail he post , all refused and return to me via hotmail o gmail ,I do not know why ?
Please Petar ,what happen

bulgarian gpr

sorry I copied all refused email regarding gpr systems, so phazitron was also in my post.

but if you have read all in my post:

----- Transcript of session follows ----- <[email protected]>... Deferred: Connection refused by bulgaria.com.
Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old

------------------------------------------------------------------

Anyway, Valchev was responding now, but he did not sent more info as I can see on his website. The main problem to operate his gpr will be the unshielded antenna and the missing approvement by telecom authority. The gpr from Valchev is a transmitter, homebuilt, no emf tests already done.
I guess everybody will have a lot of problems when importing with the customs.

As long as Valchev is not presenting more technical data this gpr are useless outside bulgaria or other balkan countries.

I think it will be a better way for Valchev to sell schematics or kits so we can build the gpr by ourselve to avoid telecom regulations.

@ Valchev: are there any user outside the balkan countries we can ask about customs, telecom a.s.o.?

[Valchev]

The mail to www.bulgaria.com - [email protected] did not work in few days actually. I do not know why. The E-mail [email protected] is not my.
Please use e-mails : [email protected] , [email protected] or send mi Private Messages, or write here.
Apologize for the trouble.

[Seeker]

----- The following addresses had permanent fatal errors ----- <[email protected]>
(reason: 550 Message was not accepted -- invalid mailbox. Local mailbox [email protected] is unavailable: user not found)

----- Transcript of session follows ----- ... while talking to mxs.mail.ru.:
>>> DATA
<<< 550 Message was not accepted -- invalid mailbox. Local mailbox [email protected] is unavailable: user not found
554 5.0.0 Service unavailable

-------------------------

----- Transcript of session follows ----- <[email protected]>... Deferred: Connection refused by bulgaria.com.
Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old

Dear UNREGISTERED !
If you read carefully Valchev's website , then you will find some e-mails : [email protected] , [email protected] , [email protected]

So, there isn't [email protected] there!

Please do not spread alarming news or be panic. Some people here had weak hearts.

email

----- The following addresses had permanent fatal errors ----- <[email protected]>
(reason: 550 Message was not accepted -- invalid mailbox. Local mailbox [email protected] is unavailable: user not found)

----- Transcript of session follows ----- ... while talking to mxs.mail.ru.:
>>> DATA
<<< 550 Message was not accepted -- invalid mailbox. Local mailbox [email protected] is unavailable: user not found
554 5.0.0 Service unavailable

-------------------------

----- Transcript of session follows ----- <[email protected]>... Deferred: Connection refused by bulgaria.com.
Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old

[Valchev]

Еxcuse me! I answer to every E-mail that I receive. I do not know why I have not received Yours E-mail. If you write here any E-mail, i will reply to you, or write yours questions here.

absolutly no response

Beware, there is no response from the bulgarian producer at all!
I sent a lot of mails, no answer.
I dont want to think about what is happen when I transfer money to this country.
I guess this people are not serious.

Or the dont want to make business with me.

Anyway, lets discuss about the selfmade GPR

[schatzsucher]

which is the price

[Valchev]

Yes

[schatzsucher]

are you interested to sell a gpr?

[Valchev]

Better test on real objects before to buy . If I do not make mistake you can not buy new commercial GPR with GOOD DEPTH less than USD17000.
If you buy, could you make some tests, experiments on a real objects and place the radargrams and the photos here.

[romtech]

Design Pulse circuits

The hardest part for me would be generating the precise sampling pulses.
Any jitter in the pulses would destroy the signal.
For the time scales involved, I would need sampling pulses under 1 ns, maybe a few hundred ps in width. I wouldn't know how to start doing this.

I guess you could switch hundreds of volts with special mosfets. Kilovolts might require capacitive discharge into special pulse transformers and pulse forming circuits. This would be another job that I would need to hire and Electrical Engineer to get done.

I've seen GPR units that are just under $10,000.
Spending $10,000 to $20,000 might be the cheap way to go.

Thank You for your input.