TESORO GOLDEN SABRE

[Max]

Ok, LM393 are open-collector outputs, so C24 charge slowly through R54 when both U106a and U106b outputs go high. Without R47, R55 , should discharge very quickly when outputs go low-- with R47, R55, discharge slower. So R47, R55 should affect audio somewhat. I'll try to experiment and find out.

-SB

Hi,
what schematic are you using ?

Kind regards,
Max

[Molzar]

Eclipse,

I think connecting them would be benificial. But you still need to connect without making ground loops.

Looks nice, can you post the files on this PCB?

Molzar

[simonbaker]

More questions on R47, R55:

TGS schematic with notch does not have R47, R55 seen in TGSL1265 schematic.

Ivconic PCB not have R47, R55 either.

If no R47, R55, then what good is C24, R54? They won't work I think, not do any filtering -- C24 just follow output of LM393 and use power for no purpose (AC short to ground), maybe make power supply spikes when output flips too.

Am I misunderstanding?

What is best to do here?

Regards,

-SB

Ok, LM393 are open-collector outputs, so C24 charge slowly through R54 when both U106a and U106b outputs go high. Without R47, R55 , should discharge very quickly when outputs go low-- with R47, R55, discharge slower. So R47, R55 should affect audio somewhat. I'll try to experiment and find out.

-SB

[simonbaker]

I did some changes on the board according to my components footprint,
and added the ground plane. There is only one connection b/w the gnd plane
and ground traces (left bottom) as Ivconic noticed thus will reduce noise.

But here is problem - the plane in the center of the board isnt connected,
so can i add some more connections (not just one, w/o worring from noise increase?)
or it's better the leave it this way

What software are you using? (it looks good)

-SB

[eclipse]

I did some changes on the board according to my components footprint,
and added the ground plane. There is only one connection b/w the gnd plane
and ground traces (left bottom) as Ivconic noticed thus will reduce noise.

But here is problem - the plane in the center of the board isnt connected,
so can i add some more connections (not just one, w/o worring from noise increase?)
or it's better the leave it this way

[simonbaker]

C20 -- wrong side?

C20 looked like in strange place to me at first -- why across battery instead of voltage regulator output?

I thought: maybe speaker causes spikes, want to smooth out.

Now I study Lobo schematics from Darko (page 68 of this thread). 220 uF capacitor is on output of regulator, not input.

In TGSL do we have C20 on wrong side of LM7808 regulator? It works, but is it best?

Regards,

-SB

[simonbaker]

R47, R55 with TGSL1265

More questions on R47, R55:

TGS schematic with notch does not have R47, R55 seen in TGSL1265 schematic.

Ivconic PCB not have R47, R55 either.

If no R47, R55, then what good is C24, R54? They won't work I think, not do any filtering -- C24 just follow output of LM393 and use power for no purpose (AC short to ground), maybe make power supply spikes when output flips too.

Am I misunderstanding?

What is best to do here?

Regards,

-SB

[simonbaker]

Hi Simon and others,

LM317 is not convenient. To much drop-out voltage difference. LM2941 is good. LM2931 is also ok for max. 100 mA currents.

Aziz

Yes - LM2930T-8.0 was in earlier TGS schematic (one with notch) -- that is good also.

Eclipse - your 9.6 v battery pack should be OK with one of these low dropout regulators. Just seems like a waste to use 12 v to get 8 v with rechargeables my opinion. That is assuming you have enough milliamps either way.

[Max]

I gave up on using the battery holders. I had 2x9V battery housings, which i was going to use. I bought 10 x 1.2V MiMH smallest type I could find and was able to fit only 8 of them. So I made 12V pack, and I will use standard setup.
Too bad for the holders, they were fitting nice in the box.
--
Any good schematics for battery charger?
Next to do are the 2 coils.

Hi,
I've posted before some small and easy schematics for them using lm317.

This is a bit off-topic here so I'm posting a new thread in "general electronics".

Kind regards,
Max

[eclipse]

I gave up on using the battery holders. I had 2x9V battery housings, which i was going to use. I bought 10 x 1.2V MiMH smallest type I could find and was able to fit only 8 of them. So I made 12V pack, and I will use standard setup.
Too bad for the holders, they were fitting nice in the box.
--
Any good schematics for battery charger?
Next to do are the 2 coils.

[Aziz]

Hi Simon and others,

LM317 is not convenient. To much drop-out voltage difference. LM2941 is good. LM2931 is also ok for max. 100 mA currents.

Aziz

[simonbaker]

nope not enough place for 10 batteries ( i am using 9V housing which can hold up to 4 cells 1.2V each) do you think the lower voltage will be a big problem?
fully charged 8 batteries can give around 11.5V .. ( 8 X 1.44V) enough power for the speaker, i suppose. it will go down to (10V when they are discharged)
Google can search better than the forum search, argh
so i found that its discussed - ~30mA w/o sound ~60mA with sound

From looking at NiMH discharge curves, I think you should design for 9.6 even 9.4 volts low battery to really get the most from the batteries - 10 v cutting too close I think, leave too much energy in battery.

You can do it with lower dropout regulator. I look at spec, LM317 prob won't have enough headroom to work well, my opinion. I harp on LM2941, looks brilliant, but I only find as samples so far; of course, adjustable so need more parts. Maybe another type like it somewhere.

Cheers,

-SB

[simonbaker]

Hi,
I meant 27m7, though 27m2 is good also for the purpose and really more easy to find.

Here's TI page of it:

http://focus.ti.com/docs/prod/folders/print/tlc27m7.html

though STM made it too, at least I think so.

Kind regards,
Max

Thanks, very valuable these alternatives, never know what parts available.

-SB

[Max]

nope not enough place for 10 batteries ( i am using 9V housing which can hold up to 4 cells 1.2V each) do you think the lower voltage will be a big problem?
fully charged 8 batteries can give around 11.5V .. ( 8 X 1.44V) enough power for the speaker, i suppose. it will go down to (10V when they are discharged)
Google can search better than the forum search, argh
so i found that its discussed - ~30mA w/o sound ~60mA with sound

Hi,
well actually could be 30mA also: depends on components you use... but when on sound could be MUCH more than 60mA as I explained: depends on setup ...speaker etc

This of above is true for TGSL.

In TGS the no-sound consumption is about 10mA higher cause of the notch sub-system that's powered all the time.

You must also add about 5-6mA due to monostable operations, but you can disable it by switch and save battery when don't use or do not implement at all if not needed.

So, suppose you use TGSL+monostable expect currents at no sound of also 35-36mA , and much more when it sound.

That's why I suggest using at least 500mAh batteries... cause if you've a lucky day you'll drain totally a say 200mAh battery in really few time... do you understand me ?

Kind regards,
Max

[Max]

8 * 1.2 = 9.6, how get 12 v? Did you mean 5x1.2 packs?

Can anyone say what current TGSL draws normally?

Regards,

-SB

Hi,
TGSL is not power hungry... requires 23-25mA when no sound, to power op amps etc

When it sounds the current depends much on your setup, including speaker type. When using headphones this is not an issue... cause consumption is few more than 25mA.

When setup is big draining speaker...using e.g. monostable... I saw also 200mA peaks there ! No good that way...I mean sound is like an horn in your ears but battery drain is TOO MUCH.

Usual safe, good limit is around 75-100mA.

In the 9V alkaline example , a duracell is around 500mAh so will last about 14.3 hours at 35mA average (considering it sound from time to time, when you switch on or locate targets).

Kind regards,
Max