IDX-PRO+VDI

[golfnut]

jpg

this

[golfnut]

Trying to assenble the IDX last night. Some discrepancies on the schematic vs PCB and assenbly photo on post page 23


on the assy photo - The Red Speaker wire appears to go to a circular pad - it doesnt.

On the schematic, have look I deleted what I dont think is there.

plus questions.


eg why is what I call the Disc pot a trimmer? (low LHS)
Whis is the Pinpoint channell on all the time - just Disc CH goes off for pinpoint on button.
etc

s

[Schatztaucher]

I might have to change R24? 1mohm to 1.5 mohm ? as in the circuit diagram?

[Schatztaucher]

hi at all,
I wonder if I miss a change. idx of beeps. but not as it should. I miss a change? can someone tell me how I set the idx in the beginning right? (i mean the potis)
maybe one of the procedure-running.
first: switch on
secound: ....
third: ....
etc.....

[szucs_g]

on ground

I was on ground. IDX is marked nicely. I found it cartridge vagina, old 10 penny ones (30 of his years were Hungarian changes, the forint was so valuable, that 40 pence were a croissant...). That trouble of mine with him, that onto rusty iron gives an off-key mark. For you too?

[golfnut]

Hi Max - you appear to be transmitting on 24kHz


This design is for approx 6.5kHz - Add about 1uF see where you go.

When you get Tx right it may get easier.

S

[der_fisherman]

Hi Der Fisherman,

I have tried all combinations for coil connections and only one combination appears correct.

As I understand it, there will be only one correct connection. Good that you have found it....

[maxfly]

Hi Qiaozhi,

are you refering to the caps in parallel with coil connections (image) or C1?
I have tried many combos for parallel caps.

Max

[maxfly]

Hi Golfnut,

check out the scope shots and see what you reckon.
would love to try another coil if i could!

Max

[maxfly]

Hi Der Fisherman,

I have tried all combinations for coil connections and only one combination appears correct.

[maxfly]

that didn't work!

here they are

[maxfly]

The scheme is correct, the Silver Dog PCB are correct. This detector works well with Whites coils 6000, XLT, etc and with the coils have been constructed DD manually. With solenoid Fisher also works well if properly set the resonance frequency and the phase angle. You have to look for suitable condensers for coil Fisher.

Thanks Eduardo,

Again you are dealing with a beginner so may I ask for some definitions and locations on the pcb for solenoid and condenser?

I have a dual channel scope but can only get one channel working at the moment so here are some shots of the TX and then RX U1/pin 6. Do things look Bad?






Regards,
Max

[Qiaozhi]

Pot were supplied by silverdog and are linear.
When I said iron goes first, I meant after coins and pull tops are discriminated. Coins are first to disappear.
I think the schematic off silverdogs site and other diagrams are correct, at least they mostly correlate.
Could I be looking at a problem with the Fisher coil? Frequency/phase angle
Ivconic seemed to get it working, maybe he has some experience with this issue.

Regards,
Max

It sounds like you need to change the RX capacitor to get the correct phase-shift. You'll really need a scope to do this.

[Schatztaucher]

hi all,
@ Eduardo: thank you for your tip. I just replaced the resistance with a potentiometer 1kohm. unfortunately, has not changed. my idx does not work still. I think I give up.

[golfnut]

Can U get hold of a scope?

Can U confirm operating frequency of TX - freq of Tx affects the phasing through the RC delay ccts..

Can U borrow someones detector to try their coil with it.

S