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I recently ordered some of these motors:
TMM
guessing that they might be the same as the motor that I used in the Weslake Eagle.
Well, perhaps they are - the motors are identical in appearance, have the same odd snap-in type connections, the same 64 dp gear and the (removeable) rubber pad on the shaft end. The numbers, however are different; MJ413A for my old motor and MJ421A for the recent purchase.
I did a quick and dirty experiment - checked the no-load current at 3, 6, 9 and 12 volts. Based on the average of three samples of each, the results are identical, 0.10, 0.13, 0.16 and 0.21 A at the respective levels. Several of the motors showed a 0.01 A difference depending on direction and one measured 0.21 A in one direction and 0.23 A in the other. (My power supply reads to 0.1 V and 0.01 A) For comparison, a TSRF motor, unloaded, draws 0.33 A @ 12 volts and a beardog motor pulls 0.11 A @12V.
In addition, the motors "sound" the same - I have a small optical tach but no disk for a 1.5 mm shaft (add to the project list!).
My guess is that the motors are functionally equivalent despite the different numbering but - I have not tried one in a car so the above is all the data I have.
I just spoke with the vendor and they have 200 of them currently in stock
EM
TMM
guessing that they might be the same as the motor that I used in the Weslake Eagle.
Well, perhaps they are - the motors are identical in appearance, have the same odd snap-in type connections, the same 64 dp gear and the (removeable) rubber pad on the shaft end. The numbers, however are different; MJ413A for my old motor and MJ421A for the recent purchase.
I did a quick and dirty experiment - checked the no-load current at 3, 6, 9 and 12 volts. Based on the average of three samples of each, the results are identical, 0.10, 0.13, 0.16 and 0.21 A at the respective levels. Several of the motors showed a 0.01 A difference depending on direction and one measured 0.21 A in one direction and 0.23 A in the other. (My power supply reads to 0.1 V and 0.01 A) For comparison, a TSRF motor, unloaded, draws 0.33 A @ 12 volts and a beardog motor pulls 0.11 A @12V.
In addition, the motors "sound" the same - I have a small optical tach but no disk for a 1.5 mm shaft (add to the project list!).
My guess is that the motors are functionally equivalent despite the different numbering but - I have not tried one in a car so the above is all the data I have.
I just spoke with the vendor and they have 200 of them currently in stock
EM