Historical Detectors & Modifications

[Norvic]

Perhaps of interest, a place to collect info of detectors from our past and their modifications. There were a few homegrown detectors about in the 80`s in OZ, their manufacturers no longer operating, perhaps also were others throughout the world, these were "the building blocks" of the sophisticated machines we use now. Some like the Goldseekers 12000 which lead to ML, and another that enjoyed some popularity was the Bridgewright.

This photo is of a Bounty Hunter RB10 that has a added pot on the front near coil plug, I believe this modification may have come from not yet ML technicians back around 83-84, unfortunately I`ve lost the operator instructions which had a extra page explaining the use of this pot in GBing the detector.

[gambler]

geez that looks like its powered by coal or steam or something.

[jasong]

 How about a couple decades earlier still?  This is the new toy I just bought, it's a Fisher T-30 and I think it's from the 1960's and its probably my favorite detector I own now, seriously this thing looks straight out of an old sci-fi movie and I love it.

Never seen another one like it and I'm wondering if it's one of the last ones in existance? Only reference on the internet to it is this one I bought. Funny thing about metal detectors, the antiques are dirt cheap even if they are rare!

I haven't got it running because it takes some weird obsolete batteries but when I get time this summer I'm going to build a voltage converter for it and give it a good run in the park, maybe a nugget patch for a bit of humor too if I ever get out again. I don't think it was ever used more than once or twice and then put away.

 

[Norvic]

Wow, case and all, that is impressive.

[Guest Paul (Ca)]

That's an old bounty hunter, have no idea what the added pot near the shaft is for? Non the less, beautiful piece.

Jasong, yeah that's a FisherScope T-30. I have two of those models, a simple 9-volt battery will replace the old original battery. Auctally collect vintage detectors, have most of the earlier FisherScope models and other brands as well.

Congrats with the vintage detector find!

Paul

[jasong]

Paul, have you tried giving it 12v? Near as I can tell the original battery was 12v but it's hard to determine since they are all long gone (one is a mercury cell for instance). That's cool you have some, I couldn't find any reference to the T-30 existing at all other than this one (literally the only pic online is of this actual machine), all the other stuff online was T-25 or T-20 or something.

Any idea what year its from? The Fisher Labs phone # in the manual is only 5 digits long!

[Guest Paul (Ca)]

Hello jasong,

Let me open one T-30 up, but from memory although some of the older TR's from Fisher Scope a 9-volt battery will operate the unit even when it was suppose to operate off 12 volts.

I'll get back and share more with the T-30, hopefully later today.

Believe 1969 or 1970 the T-30 was introduced, banking on 1969 though because early seventies Fisher was switching over to the FisherScope Explorer and a couple of other beefer TR's.

Thanks for the info,

Paul

[Inventiveman]

The knob on the front of the RB 10 is Variable Speed Retuning (VSR). It was a mod provided by the importers around 1983-4. This helps to smooth out threshold sounds from highly mineralised ground. Think of it as Auto tuning on some other makes -VSR minimum =Manual, VSR Maximum=Auto, other positions=in-between.

The Red Barons were one of my favourite detectors in the early 80's and are very good in highly mineralised ground & on the wet salt sand eg beaches. I've found lots of gold & coins in both locations with mine. I still use my RBs (5 &10) on the beach and turned up a lot of silver coins & a sovereign after the severe storms a few months ago with my RB5. It's really great on the wet salt sand in SPD discriminate BUT set the discriminate level to its minimum level otherwise you're very likely to miss gold jewellery.

A tip for the old goldfields:

Where there's a lot of ferrous junk: the SPD motion discriminator works very well in mineralised ground IF USED CORRECTLY unlike a TR discriminator which DOESN'T work reliably in mineralised ground.

To use SPD correctly: - search in the ALL METAL mode - set threshold low but audible - set discrimination level to minimum - preferably set VSR to minimum.  When you get a signal, pinpoint the target & remember or mark where it is - (important) re-adjust the ground balance at the side of the target -- switch to SPD (with either the switch or the button on the handle) - step back a foot from the target - start swinging the coil parallel and close to the ground between your feet & the target - slowly approach the target while swinging the coil as you listen to the threshold sound. The threshold will do one of FOUR things as the front half, and then centre, of the coil starts to pass over the target:

1. Increase & give a solid long sound - passes discriminator, DIG it.

2. Stays the same - deeper than the discriminator can reach. Remove some dirt & retest.

3. Sounds erratic - likely to be iron but not always so DIG it.

4. Decreases or stops -very likely to be iron especially when a small target. Leave it.

Leaving such a target may very occasionally miss a piece BUT the time saved digging and locating hundreds of pieces of small iron gives you much more time to find non-ferrous targets including nuggets.

REMEMBER detecting is being banned in more and more places because people are not filling in their holes. SO PLEASE FILL IN ALL YOUR HOLES

[Norvic]

Many thanks for that, yes I was contacted by importer about mod sent it back for mod, by time I`d received it back had a Garret A2B which in those days was loosely equivalent to the Z today. Whilst I did use it after mod, it just was not up to the A2B in the gold field. But it did well before the A2B and I prospected with fellows using Whites 6000D & Garett DSs and believed it had the edge on them.

You have solved what Mod was for as I`ve lost all documentation and a lot of Memory. ie brain is fragmented badly.

[Au4Gold2]

Here's my first detector I bought when I was 11 ..bought it from a magazine. Found many coins in and around churches and some silver. Bought it in 1980 I still think Detectron is in business down in Southern California and last time I looked they advertised it as a man-hole detector. When I bought it of course it was a treasure seeker...but technology obviously surpased  their ability to compete in this market of treasure , coins and gold nuggets. Funny thing is I paid around 145.00 think today they are around 450.00..And whats with the red color many early detectors had....Garret had the right color..green blend in with the environment