Compass 77b info wanted

[ZOUjiarui]

Does anyone have information on compass 77b?
Coil or PCB information

[kt315]

in a folder COMPASS in the archive.

[ZOUjiarui]

I can't find it. I just saw the schematic

[kt315]

https://drive.google.com/file/d/1pcn...ew?usp=sharing

[ZOUjiarui]

https://drive.google.com/file/d/1pcn...ew?usp=sharing

I sent a permission request. Thank you

[Melbeta]

I do not believe you need permission to print out a copy. But you do need permission to extract it from the .pdf file into a .jpg or other graphic file. I doubt that KT315 secured that particular schematic from extraction from the .PDF file. So just print out a copy of it and use it for whatever purpose you need...

Now the 77b did not have discrimination built inside it. It was pure TR all metal mode, running at 100 KHz frequency. The coil was a special DD coil winding.

Shortly after that 77b unit, Compass did come out with a variation of the 77b, having discrimination built into it, and it was called a Judge 1 and the better model was the Judge 2. Now the very first model, Compass used the remaining Metal/Mineral tuning parts, from the older 77b detectors, inside the first Judge 1 and Judge 2. But as they used them up, the second version dropped the Metal/Mineral tuning parts.

But they did not have the old DD coil from the 77b in it, but instead created a one of a kind coil, for the Judge series models, similar to the DD coil, but a different winding arrangement. It also was 100 KHz frequency, but did not have the metal/mineral tuning in it, which was in the 77b models.

The older 77b had a tuning called Ground Condition Control, which was kind of like a CB radio squelch control, you could back it off, and detect in magnetic mineral ground, without hearing the static noise from the magnetic black sands. Thus one could search either in MINERAL setting, find the black sands deposits, dig down to them, pan or detect the black sands. Now the metal/mineral control GCC tuning adjustment, could let you search the mining lands which had magnetic black sands in it, and still find good relics and coins using the METAL setting. So you see, the 77b was a pure all metal detector, with a metal/mineral control, and with the GCC control, one could use it to find gold nuggets and/or magnetic black sands...

Only the very first Judge series model (Judge 1 and Judge II), still retained the Metal/Mineral tuning pot.
Melbeta

[kt315]

i see some info on 77B in this section of a forum https://www.compassforums.org/Compas...td7626976.html

[ZOUjiarui]

Thank you very much.

[ZOUjiarui]

[ATTACH]56317[/ATTACH

[ZOUjiarui]

[ZOUjiarui]

I hope this works.