The results are in!! (TG-CD current test)

[kid_rondeau]

Hey all!
I finally got to work on making an amperage testing device for my TG-CD. It's basically a 16" extension cord for the DC end, but one of the two wires gets routed through my ammeter. A bit of a laborious approach, admittedly, but this way I didn't have to cut or desolder anything.

I hooked it up just minutes ago, and monitored current consumption at various system states. Please observe:

Both decks off: 0 mA (duh...)
TG16 on, TG-CD off: 0 mA
TG-CD deck on, TG16 off: 330 mA

CD Games

At CD Game Startup Screen: ~600 mA
After pressing RUN, right as CD program starts loading: ~1000 mA (brief spike)
While CD loads, searches, etc.: ~850 mA
While loading saved file: ~850 mA
While playing CD game normally: ~750 mA
While saving file: (no change)

Chip Games

Title screen, normal play, etc.: ~600 mA
While loading saved game from File Cabinet: ~600 mA (I noticed a slight drop once or twice, down to 570 mA.)
While saving to File Cabinet: (no change)


In conclusion, the absolute most current draw observed from this system was 1000 mA, 1.0A. I feel this is consistent with my stated theory earlier, that the Voltage and Current numbers printed on the adapter's label were deliberately reversed as a proprietary measure:

11VDC -> 1100 mA
1.53A -> 15.3V.

In both cases the numbers worked out exactly as I predicted (well, figuring NEC put the max current at 1100 mA instead of 1000 mA for product safety reasons).


So! For those of you who are still looking for a TG-CD power supply (and who trust me enough to take my word for it...) you need only find a 15V, 1.1A AC adapter.

QED.

[ATOM]

15v may not even be needed.  check the voltage regulators you can usually go down to about 120%-130% higher then the output voltage.  a 7805 (5v regulator) can usually take voltages down to about 6.5v-7v without any issues.

[nat]

The adapter I've been using and recommending for the better part of a decade is a 12V/1.5A adapter. It's specs are similar to the printed specs of the original and it works. Well.

[kid_rondeau]

To Nat's point about 12V being sufficient, I was inspired to test out the absolute minimum voltages at which the system will function properly. I used the variable DC power supply on my dad's old breadboard/experiment kit which I inherited.

Conclusions:
A minimum of 8.5VDC is required for a chip game to play properly. The system will turn on with slightly less than this, but the colors will be dark and the games are prone to glitches.

A minimum of 10.3VDC is required to get the CD unit to play a CD game, but its performance is overall sluggish. I got normal, acceptable performance from 11.0VDC and higher.

For the heck of it, I checked the load times using 12, 13, 14, and 15 Volts, and saw no improvement over 11.0V.


So, Nat was completely correct in recommending and adapter that puts out 12VDC/1.5A. The voltage will ensure reliable performance even if there is a drop in the AC to your house, and the 1.5A monster will happily give the TG-CD all the current it wants, even if it's never more than 1.0A.

...not that Nat needs to be told he was correct...I just thought he might like to hear me say it.

[ATOM]

To Nat's point about 12V being sufficient, I was inspired to test out the absolute minimum voltages at which the system will function properly. I used the variable DC power supply on my dad's old breadboard/experiment kit which I inherited.

Conclusions:
A minimum of 8.5VDC is required for a chip game to play properly. The system will turn on with slightly less than this, but the colors will be dark and the games are prone to glitches.

A minimum of 10.3VDC is required to get the CD unit to play a CD game, but its performance is overall sluggish. I got normal, acceptable performance from 11.0VDC and higher.

For the heck of it, I checked the load times using 12, 13, 14, and 15 Volts, and saw no improvement over 11.0V.


So, Nat was completely correct in recommending and adapter that puts out 12VDC/1.5A. The voltage will ensure reliable performance even if there is a drop in the AC to your house, and the 1.5A monster will happily give the TG-CD all the current it wants, even if it's never more than 1.0A.

...not that Nat needs to be told he was correct...I just thought he might like to hear me say it.

yeah system itself internally uses prolly 7v right off (prolly stepping down further elsewhere) and the tg-cd uses a 9v regulator before it goes anywhere.

i can safely say a 12v 1.5a power supply would be plenty and easy enough to find.

[nat]

...not that Nat needs to be told he was correct...I just thought he might like to hear me say it.

Yay me!