The Apollo is from the early 70's. it was made by Whites. Whites made a lot of units for different "brand" names.
I will make a point to post some photos after the convention. As far as a date goes there really isn't any. It just depends on what the individual unit is. I personally collect pre-discriminator models. That limits it to the mid 70's. I have Garretts first discriminator. It's a BFO. The only difference I can see between it and another "non-disc" is the meter. The electronics look the same. Instead of tuning it to the side of the meter, it is tuned to the center. One way is good and the other bad. I think it just works off the metal/mineral null deal. You older TH"ers will know what I am talking about.
I have not heard of the Little Monster but will keep an eye for it. When I go to hunts people will often show up with an old detector to see if I am intrerested. Occassionaly I find one I don't have. Picked up a Dtex Professional in mint condition still in the origianl packaging that way. Don't have all the Garrets but I am only missing one Fisher of having the whole line. T-10, T-15, T-20, T-30, T-120, T-122,TH models, Orion models, M-70 and explorer. I may have missed some there. Have quite a few Dtex and Detectron as well.
Here is a piece of trivia. The Detectron company made gieger counters. They started making a few detectors and it took off. The company was sold and continued under the same name. Curt Cassingham then opened up Raytron to build detectors. After a short time he changed the name to Rayscope. I have a Detectron made by him and a Rayscope and they are identical other then the color. So Detectron and Rayscope were making virtually the same unit. Don't know how that worked out. I also have a Raytron. That is probably a real tough one to find as it was made under that name for such a short period.
Just picked up an old Goldak. Not sure on the date. It could go into the 50's. The tuning control is on the coil!
I have to take my son to scouts. back later.
Mark S.
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