Seeburg TASU2

I am in the process of getting my Transistorized Auto Speed Unit-2 working with my Seeburg DS100. When I connect the TASU-2 to the phono and select a 33 1/3 record the 33 1/3 record is selected and mounted. At this point the whole operation stops. The trouble shooting guide (Page 372) Item 2 shows that this will occur if C or A contact fails to close. However with the power relay cover off I can see and hear the contacts close.

I think this may be my problem, as it appears that with the 33 1/3 record mounted that it loses all power. On page 2465 of the manual, reference is made to the "clamp arm switch" that controls the power relay in the ASU . "S" contact has 1/32 gap in play position with standard 45 RPM record clamped on turntable and is closed in scan posiition and when 33 1/3 RPM record is being played back. (I inderstand how to use a feeler gauage to make this adjustment) It further states that the contact "MUST HAVE 25 GRAMS OF PRESSURE WHEN CLOSED". I do not understand how to determine when there is "25 GRAMS OF PRESSURE"?

In lieu of the "25 GRAMS OF PRESSURE" measurement, could I select the 33 1/3 record, wait for it to be mounted and all action to stop and then slowly start turning the adjustment screw until the contact closes and the record begins to play?

Anyone have any ideas?

Thank you
Darrell

Hi Darrell,
Your problem is internal to the TSAU. The "clamp arm switch" is operating as it should, if the motor is stopping when a small hole record is fully mounted to the turntable. The clamp arm switch's function is to excite the relay in the TSAU, which turns the TSAU" on". If the clamp arm switch were not functioning as it should, the record would play at 45 rpm. Ron Rich

Thanks Ron. I Now have two working TASU2! To preserve loess units, would it make any difference if the TASU is constantly left plugged into the TASU, or would the TASU life span be prolonged by leaving them unplugged from the TASU when no 33 1/3 records are going to be played?

Darrell

Darrell,
That's kinda the "chicken and egg question". In all honesty it should not matter too much, as the TASU is not "powered" until the relay is energized---
However, it is my thought that any electrical item is better off left un-plugged, if it is not going to be used in "awhile"--
BTW--what was the problem here--the clamp arm switch ?
Ron Rich

I think when I am not going to be playing 33 1/3 records I will leave the TASU2 unplugged and hopefully this will extend the life of the TASU2 units.

A person gave me a working TASU2, so the problem was not in the clamp arm switch. Two TASU2's to go! Looking at doing a recap and see if that will make another one work.

Darrell

Anyone have a source to obtain the mica insulator that fits under Transistprs Q751, Q754 and Q755 for the Seeburg TASU2?

Thanks
Darrell

Darrell,
Yep--how many thousand would you like--do you have the proper heat sink grease ?
( If you have powered up the unit without the mica, the transistor(s) are ruined )
Ron Rich

Ron

It depends on how much they cost, if reasonable, 9 plus a tube of the proper grease.

Unfortunately, this is the TASU2 that would select the record and then when it was mounted would come to a stop, as explained in my first post! I made the inspection for the mica insulators after your adicde that they should have them

What do transistors cost and where can I find them?

Thanks
Darrell

Darrell,
Please contact me off list- ronnnrich@yahoo.com
Ron Rich

I received a capacitor kit from a seller listed on this site. I do not want to damage the TASU2 and am wondering if these caps are within an aceptable range. Is there a rule of plus or minus and go above or below to follow.

Manual Calls for

C751 500uF 50 Volts
C752 800uF 30 Volts
C753 9 uF 6 Volts
C754 100 uF 100 Volts Non-Polarized Lytic
C755 0.05uF 200Volts

Dealer Supplied

C751 470uF 50 Volts
C752 1000uF 50 Volts
C753 10 uF 25 Volts
C754 100 uF 100 Volts Non-Polarized Lytic Marked tested. This had two different size capacitors hooked up positive lead to positive lead. (Parallel?)
C755 0.47uF 250Volts

In regard to C754, one capacitor is 150uF 100 Volts and the other one is 220uF 100 Volts. From what I have read the formula to see the value of this is: Ct= C1+C2 ++++++ So, 150uF + 220uF = 370uF not 100uF and as I understand it,you get the voltage by taking the lowest value, which in this case since they are both 100 would be 100 Volts. What am I missing that I get 370 uF and the seller gets 100uF?

Thanks
Darrell

Hi Darrell,
All caps are well within range--
Except MAYBE the non-pol-- I can not recall the formula to make a non-pol--but I do remember that two 100 uf caps wired + to +, divide, and make a NP 50. I think the voltages add together in this case--
So, going from my spotty memory, this would be within range also--
Might call the supplier and ask how it's done--
Ron Rich

Ron

Thank you. I ran into a friend that said the prope formula for two polarized caps hooked up in series would be C1 times C2 divided by C1 + C2.. When I used this formula I came up with 89.18 uF. From your assurance that the others are within uF range, I assume this one is also within range, unless a different range exists for non-polrarized caps? My friend was not sure what determined whether two polarized caps were polarized or not polarized.

Good idead about calling the supplier, as he is helpful, will give that a try.

Darrell

Method of determining the value of two capacitors in series is by using the following equation:
C = (C1*C2)/(C1+C2)

For example, if a 470pF capacitor is connected in series with a 47pF capacitor, the total capacitance is equal to (470pF*47pF)/(470pF+47pF) = 42.7pF. This result could have been obtained using the reciprocal equation: 1/C = 1/470pF + 1/47pF = 1/42.7pF, therefore C = 42.7pF. Again, either equation may be used, depending upon which is more convenient.

So I think I understand this & came up withthe figure 89.18uF. Wow, life is simple! OOPS, wrong!

Now I come across this:

"How do you make a non-polarized electrolytic capacitor?
Take two electrolytic capacitors of the same voltage and capacity, connect the positive leads together and connect the negative leads to the circuit. Just keep in mind that this will reduce the cap. value by half (2, 1000uF caps = 500uF) Also the voltage of the circuit should not exceed the voltage of one of the caps."

According to this I would have C1(150uF) + C2(220uF) = 370uF reduced by half =185uF.

My problem is that it can not be both, so which one is correct 89.18uF or 185uF?

Darrell

If you plug the 1000uf caps in your example into the formula, the answer is 500uf. You had the correct answer of 89uf for the two caps that came in your kit. It will work for your non-polorized cap. To be totally correct, using two 200uf caps with the positive leads tied together would be exact. On one half of the AC cycle, one cap conducts. On the other half cycle, the other cap conducts. Install the caps in your kit, they will work.

Guy's,
Thanks for the "memory jog"-- Ron Rich