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Difference between the 77b and 77IB is ??
Posted by: Tom_in_CA
Date: August 28, 2016 08:10AM
Can anyone tell me what the difference was between the Compass 77b, and the Compass 77IB ?

I know that the "i" in IB stood for "induction balance". And I always assumed that all the "77s" were the same. Is there a difference in the ones where it had the "i" in the name/title ?

Followup question:
Posted by: Tom_in_CA
Date: August 28, 2016 03:33PM
On one of the 77b's I have, that simply has the decal "77b" [no "i" in there], it has battery pods for 3 sets of double A 4-pack batteries. Ie.: the 4-packs each (4 x 1.5 volts = 6 volts total). For a total of 12 batteries to fit inside the machine. And the exterior battery check function clearly says : 6, 6, 6, on the 3 selections of battery check. Presumably for 6 volt + 6 volt + 6 volt.

But on the 77iB machine I have, I notice that the space inside for the batteries does not allow for 3 packs of double A's to fit inside . In the plastic sleeve where they intended for the batteries to fit. And on the outside, on the battery check control, it says: 6, 9, 9. I'm guessing this is because this machine is made to take a single pack of four AA's (6 volts total), and two 9 volt batteries.

Here's a pix of the outside of each. Notice that while they are both 77's, yet the battery check label is labeled differently



And the "leads" to the batteries don't tell me anything about intention. Because the connection for a 9 volt battery, is identical to a connection intended to a 4 pack of AA's:



So are there some 77's which were made to accept 9 volts batteries, while others were intended to take only AA's ?


Re: Followup question:
Posted by: fowlercharles
Date: September 08, 2016 09:10PM
Hi Tom, wasn't there also some differences in the Coils on the very early I b machines? As I recall from some Pics I saw somewhere, with descriptions I think maybe by Monte (I could be wrong) mentioned the coils being stationary, and not adjustable. I think there was one on Ebay fairly recently that bore that out also. I've never "seen" any version of the 77b /ib . I have a 94B and a couple of Coin Hustlers, and they being later of course have the adjustable coils. Just thought I would mention the coils so we could round all the bases. HH, Charlie

Re: Followup question:
Posted by: Tom_in_CA
Date: September 09, 2016 07:16PM
Hello there fowler charles . Yes, there was incompatible coils from when they evolved from iB to B. That was in about 1974. The newer coils are no longer compatible with the older ones UNLESS you are able to go inside the machine (or chord or coil, or something) and do a minor alteration. So they can be made to be compatible, but not without a little alteration of some sort.

And yes: When that changeover of coil types occurred, the new coils have adjustable angles, while the old ones were "fixed" position.

The newer B versions went a bit deeper, rejected iron better, etc.... But both of them could still do the "see through iron" trick, from what I'm told.

Re: Difference between the 77b and 77IB is ??
Posted by: reddogpatch
Date: October 30, 2016 02:03AM
Just proved that see thru iron trick today when I found a penny next to a bottle cap..AWESOMENESS..Love my 77B PRO

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