Tesoro Eldorado on the bench

[arion]

How to calibrate? Moving the coils, or other?

If the coil voltage of 0.03 mVolt, LM308 output 4Volt,
If the coil voltage 30mVolt, LM308 output from 6 to 6.5 Volt. and
a sinus signal is distorted.
If you reduce capacitor RX, TX-RX improved phase (19us-> 4us)
and also decreases the voltage output of the LM308. (Cc.2Volt)
I can not be better to reduce the voltage.

If you reduce capacitor RX, TX-RX improved phase (19us-> 4us)
RX-GEB phase poor... 160degrees



Best Regards

[sadowski25PL]

On 6pin of LM308 must be 0,6-1V.
You must calibrate to this value 0,6-1V
Try on 0,8V.

[arion]

Hi.
I using external PC scope: Type: DSO2100

I do not understand the problem.
This is the second coil.
The first coil inductance was good. But not worked well.
Discrimination was not working and poor sensitivity.
The pictures are all right? A good phase?

I change the TX capacitor. (I added 3.3 nF) Frequency 10.1 KHz now.
Sinus signals are nice. TX-RX phase delay cc. 20us.
Changed my RX capacitor. (27nF) TX-RX phase delay of 4us now.
Coil nil good, 0.03 mV AC. LM308 output of approx. 4V measured.
Take photos of the new measurement. I think not good for the RX-phase of the GEB.

Best Regards

Laszlo (from Hungary)

[sadowski25PL]

In my opinion you made wrong Coils.

Tx: 5,5mH
Rx: 6,5mH

Is better.

And small question.

What oscilloscope you using?

[arion]

Hi Ivconic, please help...

I made new DD coils, (27cm outer diam) parameters:
TX: n=100 wire 0.28mm, 7.0mH 18,2 Ohm
RX: n=54+54 wire 0.28mm 8.0mH 20 Ohm.

TX signal: 13V PP, and 10,4KHz
-Ut: -5,9V.

Sensitivity poor: 1euro 2-3cm, deo flask cc.30cm

what the error?
pictures:

more pictures

[arion]

Hi Ivconic, please help...

I made new DD coils, (27cm outer diam) parameters:
TX: n=100 wire 0.28mm, 7.0mH 18,2 Ohm
RX: n=54+54 wire 0.28mm 8.0mH 20 Ohm.

TX signal: 13V PP, and 10,4KHz
-Ut: -5,9V.

Sensitivity poor: 1euro 2-3cm, deo flask cc.30cm

what the error?
pictures:

[erolunall]

Hello

Attached Pdf format of 1265 PCB by İvconic


Regards
Erol

[ivconic]

Yes that's exactly the same i was talking about. What a nice machine! Shiny!
Pitty we are not closer and pitty i can't order (and receive) things from abroad! $250 price is much fair - can't be better and more favorably! I have exactly the same coil with my Bandido II.
Ok...for those which are in better situation than me; i suggest and recommend this offer as best buy for sure!
Regards!

[divewrecks]

Eldorado Metal Box FS

Sorry if this is not the exact place for this. Just though someone might a good unit to mod or play around with.....

I have a classic metal box Tesoro Eldorado for sale. It is in very good condition. I bought it to hunt with a guy who swore by his for CW relic hunting. I then looked long and hard until I found this one in Canada, which had hardly been used. Unfortunately my acquaintance moved away, and I was not able to again visit the sites he took me to or to learn from him about the Eldorado. I turned to underwater hunting, and that is about all I do now. I am embarrassed to say that I have only used the detector twice in the last eight years. Anyway, I am willing to part with it now. I think I paid $300 for it at the time, but will take $250 plus shipping. I think these pictures (sorry the first few are a little blurry) are self explanatory, but let me know if you have any questions. I did find an operating manual on the Tesoro site and will include a copy.

Regards,
Stan
[email protected]

http://www.hiddenworld.net/divewrecks/detector/pic1.jpg
http://www.hiddenworld.net/divewrecks/detector/pic2.jpg
http://www.hiddenworld.net/divewrecks/detector/pic3.jpg
http://www.hiddenworld.net/divewrecks/detector/pic4.jpg
http://www.hiddenworld.net/divewrecks/detector/pic5.jpg
http://www.hiddenworld.net/divewrecks/detector/pic6.jpg
http://www.hiddenworld.net/divewrecks/detector/pic7.jpg

[ivconic]

White's......

[WM6]

Very interesting tests and processing, ivconic, go continue this way.
.
Frankly, this days I'm only interested in "non motion machine".

[ivconic]

Ah yes; Tesoro Bandido II i recently got is performing a bit better than handmade Eldorado (with same size coil). At first glance i wasnt delited with BII. But now knowing it better, adjusting it more properly it is working very good! Actually, threshold affects depth in Disc mode much more than i could anticipate. Seems not "linear". In Disc mode it must be adjusted to maximum to achieve highest depths, while in All (nonmotion) mode it must be lowered to 50-60% to work properly and retune switch to have some effect at all.
Same thing i experienced at Eldorado, but BII is more sensitive in any case.
Unlike the situation at Musketeer. At Musketeer threshold is stabille and "constant"....how can i put it...."linear". Switching between All and Disc doesnt affects treshold behavior. In original setup Colt doesnt have pp mode. I changed that and turned it to Advantage. Even now switching between modes doesnt affects threshold (not significant).
So...i am wandering how to achieve same thing at Eldorado (and BII)...
It is time consuming to readjust threshold each time when modes are switched.

[ivconic]

A slice shallower than TGSL, maybe 5%. Discrimination excellent. Audio very loud and good. Stabillity perfect. Very good nonmotion mode. Manual GEB.
What to say? Very good detector.

[WM6]

Hi ivconic,, what about your nice looking Eldorado first field impresions?

[ivconic]

Fisher 1265, 1266, 1236, 1225......1210 maybe, take any of those and examine enclosure.
Gold Bug and Gold Bug II have almost the same shaped enclosures but with smaller dimensions.
Minelab Colt and XS ( also 15000,16000 and 17000) also do have very convenient enclosures....so as some Compass's and newer Cscopes...