Bounty Hunter (PNI) IB 300 PCB schematic

[cyclops]

Bounty Hunter (PNI) IB series
IB-100, IB-200 & IB-300

This article may be of interest for a those users already (or still) owning one of these mid 1970 detectors and who want to restore it. Or just start an (other) IB project.

Thread making a brief presentation of the detector series, see the following link:
http://www.geotech1.com/forums/showthread.php?t=18511
Q/A for restoring a unit, follow the above link.

Having tinkered around on these units for several years, I think it’s time to share some insights.
Basically it is a result of some efforts to restore and repair the units I got.

For someone who already got experience with electronics, it may be easy to reproduce the PCB as it is confirmed to work. However, the one who attacks this as a project may have problems to get a working coil. A sensibility of around 23 to 25 cm on a 10 Cent (Euro) coin with an original coil (air test) will probably not be matched. My efforts to reproduce a working coil resulted in only 3 to 4 cm sensibility for a 50 Cent coin. Coil data will be provided later in this thread.

The PCB works. I got one manufactured based on the Sprint-PCB file pictured below, it is working pretty well with an original coil. You may notice that the PCB done with Sprint is a bit wider (16 x 10cm) than the original PCB, original dimensions are 14,7 x 5,1 cm.

Part list will be published below.

Although the essential has been said, I have one open question to someone more advanced in electronics than I am (Don’t forget, I’m only a tinkerer.):
Can someone identify for me the different blocks (TX, RX, oscillator, comparator (?), pre amp, amp, audio and so on) on the PCB?

picture of top side of the PCB

picture of copper side of the PCB

black/white picture of the copper side (147 mm x 51 mm)

parts side of the PCB (printed file from Sprint-PCB)

parts side of the IB-300 PCB with wiring (printed file from Sprint-PCB)

[cyclops]

part list

here is the part list

[porkluvr]

Can you please post the schematic if you have it?

[cyclops]

hi porcluvr,

i just did the PCB in Sprint, I tried to do schematic but failed miserably
(that's basically one of the reasons I also failed to do a bloc diagramm)
if some one can do it: thank you in advance

cyclops

[porkluvr]

That's OK - I guessed there might have been mis-communication. Maybe somebody will be able to RE the schematic from the PCB you've provided, it doesn't look terribly complicated. (But - it won't be me.)

I have a few failures under my belt when it comes to trying to work backwards from a PCB.

Regardless, I'm sure you'll have folks wanting to reproduce the IB300 based on what you've already put here.

[Patrick]

hi porcluvr,

i just did the PCB in Sprint, I tried to do schematic but failed miserably
(that's basically one of the reasons I also failed to do a bloc diagramm)
if some one can do it: thank you in advance

cyclops

Notify me if there are mistakes.

[cyclops]

oh, wow
thank you Patrick
it will take me some time to work through ( and learn a bit, i guess)
i am impressed

[mikebg]

Induction Balanced Regenerator

IB-100, IB-200 & IB-300 are regenerative detectors. The RX coil and the TX coil are connected in iinput and output of the amplifier, forming an oscillating circuit "Induction Balanced Regenerator".
The circuit will operate better with TWIN LOOP RX coils.
The theory of operation was discussed in this thread:
http://www.geotech1.com/forums/showthread.php?t=16294

[cyclops]

coil data

the coil data can be found here
http://www.geotech1.com/forums/showthread.php?t=18273

[cyclops]

corrections to the schematic

Hi Patrick,

After a first check:
C14 (electrolytic cap) went lost somewhere: it has to be placed somewhere between +6V and GROUND
C18 got a double count:
- C18 near R44 is OK
- C18 near SPEAKER (top outer right on the schematic) has to be renamed to C16 (which is electrolytic and actually missing)
Count of caps is OK after these corrections; but I still have to check the emplacements.

All the other counts seem to be OK, but I still have to check the emplacemnets.

(to be continued)

All the best wishes for 2012 !

cyclops

[cyclops]

revision continued

Something I noticed and have to mention:
On the PCB layout pictures, the transistors are uncorrectly annotated "E B C" and it is my mistake . It's a relict from a time I tried to use substitutes for the transistors.
It shall be "E C B" and will be respected in the next revised drawing.

The rest of the drawing is correct (do not forget, I already produced a working unit).

Patrick did not copy my mistakes, so the schematic basically remains OK. I checked all the transistors in the schematic and their connections: all OK, it's correct.

(revision to be continued)

@mikebg: Thats really interesting! Did someone already try to do a twin loop RX coil like on the Pop. Electronics 1969 picture? Did we get results?

Cheers

[cyclops]

revision finished

Hi all,

It seems as there aren't any other mistakes in the schematic.
Thank you Patrick!

For my own personal convenience (my ears are the only interface to my detector) I made a basic version for those who prefer hunting without meter, thus saving two diodes (D2 & D3)and two resistors (R33 & R45).
I'll contact Patrick and look with him if he sees a need in posting a rectified scheme (see post 10 above).

cyclops

[Patrick]

Hi all,

It seems as there aren't any other mistakes in the schematic.
Thank you Patrick!

For my own personal convenience (my ears are the only interface to my detector) I made a basic version for those who prefer hunting without meter, thus saving two diodes (D2 & D3)and two resistors (R33 & R45).
I'll contact Patrick and look with him if he sees a need in posting a rectified scheme (see post 10 above).

cyclops

This is the version 1.1