Infinity The first arms that the company sold were actually Infinity branded versions of the Forrmula 4 Tonearms but in the late 70's it introduced a pivoted arm of it's own manufacture that featured a carbon fibre arm tube constructed out of the same carbon fibre material as the linear tracking arm on the The Infinity Airbearing Turntable, it is called Black Widow and is now considered something of a minor classic. It's a normally pivoted arm but features a very rigid low mass arm tube and is designed to mate with low mass/high compliance MM carts that were very popular amongst USA audiophiles in the 70's, it features a adjustable anti skating and an oil damped arm lifter and at the leas some (all ?) models featured an adjustable VTA. It is noted that late 70's models are marked just Black Widow but early 80's models are marked GF but there is no clear clue as to what the difference is, the same goes for the Mk II model that was introduced in the early 80's.
The Black Widow technical specifications are : Effective length : 237 mm. Total Cable Capacitance : 60 pF. Pickup Balancing Range : 4 to 8,5 grams. Offset angle : 21,017° (optimal 23,221°). Overhang : 14,359 mm (17,477 mm). Null Radii : 60,00 / 110,00 mm (opt. 66,04 and 120,9 mm).
JVC Did sell separate tonarms in the late 60's/early 70's, although these were seldom stocked by specialist and possibly intended more as spares. Models such as the UA-7045 occasionally turn up.
Keith Monks Sound Systems An English company that has exited more markets than most other companies have even entered. One of their products in the late 60's/early 70's was the Labratory arm, one of the first lightweight unipivots that started to appear with the introduction of the ADC ultra light pickups. Sometimes referred to as the KMAL Labratory arm (shortening of Keith Monks Audio Limited) the arm is a damped 9" model and was considered too be quite good at the time a bit like a more refined Decca International arm perhaps and indeed according to reports this arm supposedly worked well with some Decca carts. Since the Laboratory arm has mercury damping, it is strictly speaking illegal to ship it through the post, one of the reasons it was discontinued.
Koetsu Made for a short period a conventional but finely crafted tonearm. Does anyone out there remember the name ?.
Koshin Made the GST-801, an conventional high mass S shaped arm with a detachable headshell.
Lenco The old L-75 arm from the 70's was probably only sold as spares, but it shows up NOS from time to time and is actually not a bad budget arm.
Linn This may come as a surprise to some of you, but the Basik (LV X) and the Basik Plus (LV X+) arms were something less than overwhelming when they came out and by today's standards are very outdated. It was Linn's answer to requests made by dealers that wanted a cheap and cheerful arm and cart to go with the LP12 mostly to keep it within a certain price range. If you are looking at a buying a good player with this arm second hand you should factor in that you will have to change the arm to get the most out of you turntable, even a second hand Rega 250 will be a big improvement, and if you are buying from a dealer it might be worth a try to get him to offload the arm for you (there is plenty of Linn freaks out there that will buy almost anything with that name on it, esp. here in the UK, and ANY type of Linn arm will fetch at the lest as much as a Rega so you will). If you are dead set on a Linn arm you should note that the Akito that was introduced slightly later than the Basik+ is much better and can be found used for a similar price.
Magnepan Made the Unitrac 1 arm, a low mass unipivot quite popular with some US audiophiles. Have heard that it can be difficult to mount without the correct cut-out.
Mark Levinson Sold the Goldmund T-3 arm under it's own name in the early 80's and possibly a little bit before that.
Mayware You can find the manual for the old Formula IVhere, it was a lightweight silicon damped unipivot and quite nice for that type of arm in that price bracket (it retailed for less than 100 £ originally). Apparently this arm was sold in the USA as JH Labs Formula 4 but is rarer than the Mayware version, unknown if this was OEM's by the British company or if this was a Japanese arm that both of them imported.
Michell Engineering Has never manufactured tonearms per se, but has recently sold rebadged Rega RB-250 arms with their turntables and they used to sell the Fluid oil damped unipivot arm in the 70's that I think was made for them by Transcriptors Limited.
Micro Seiki Apparently some arms were manufactured by the company itself and some were sourced for Japanese OEM suppliers. The MA-505 series was manufactured in the 70's and early 80 are usually only marked Micro and some models Micro Seiki.
Mission/Cyrus but the old britis audiophiles (the Linn/Naim types) prefer the original versions of the 774.
Micro-Trak Had a range of arms including the JC1-AC.
Pickering Had the Flux-Valve Cartridge Arm in the 60's, best left alone as it was something of a dog and even the most hardened Japanese single tiode/50's tech fans screams bloody murder when they hear that name :).
Pierre Lurne Apart from the Romeo and SL-5 arms that are now sold as Audiomeca Tonearms this French company made and earlier tangential arm called SL-3.