I suspect that for your jack socket with 5 pins, 1 of those pins is used for the common ground connection, the other 4 consist of 2 connected pairs, one pair for the L channel, the other pair for the R channel. When the plug is NOT plugged into the socket each of the 2 pins in each pair is connected together. However, when a plug is*inserted into the socket the two pins get mechanically disconnected with one of thepins in the pair connecting the the L channel (and for the other pair of pins, one of the pins connects to the R channel).
In other words, for your 5 pin socket, you need not connect to 2 of the pins & you've got to work out which of the other 3 pins connect to ground, L and R.
Phew! I bet that makes not sense whatsoever!
A
In other words, for your 5 pin socket, you need not connect to 2 of the pins & you've got to work out which of the other 3 pins connect to ground, L and R.
Phew! I bet that makes not sense whatsoever!
A
Anonymous1, Mooly and Andy.....Thanks again, you guys are the sweetest!
You guys were all right on the money with your descriptions. I am able to solder just to 3 pins, and 2 are left unused. I did decide to remove the 3.5mm jack that was soldered to the PCB. I then soldered my wires directly to the board.
After posting this I did go and buy myself a multimeter, now I just have to learn how to use it, hahaha.
Thanks again!!!!
You guys were all right on the money with your descriptions. I am able to solder just to 3 pins, and 2 are left unused. I did decide to remove the 3.5mm jack that was soldered to the PCB. I then soldered my wires directly to the board.
After posting this I did go and buy myself a multimeter, now I just have to learn how to use it, hahaha.
Thanks again!!!!
Chris,
I would love to know more about this. Did you wire your board with just with a 7.2V remote control battery? Or did you wire it so you could use a wall plug and a 7.2V battery?
I think it would be so cool to be able to make this a portable. But I wouldn't want it to be only a battery powered unit. Is it possible to wire this up so it could have both a wall charger and a battery? I am also wondering if you one could use a 12V SLA battery.
I posted a question in the boominator similar to this but never received a response. Maybe someone will elaborate here. Pretty please.
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Chris,
I would love to know more about this. Did you wire your board with just with a 7.2V remote control battery? Or did you wire it so you could use a wall plug and a 7.2V battery?
I think it would be so cool to be able to make this a portable. But I wouldn't want it to be only a battery powered unit. Is it possible to wire this up so it could have both a wall charger and a battery? I am also wondering if you one could use a 12V SLA battery.
I posted a question in the boominator similar to this but never received a response. Maybe someone will elaborate here. Pretty please.
You twisted my arm.
Here's my little project - http://www.diyaudio.com/forums/full...em-long-first-post-no-really.html#post2975887
I just used a normal DC socket on the speaker itself, found a matching wall power supply, and made an adaptor to go between the battery and the speaker.
The battery usually sits on the floor behind the speaker - once its set up its almost always stationary, so I didn't bother to make a nice tray.
You could use a SLA battery, but (as you'll see on my linked thread) there are options for far more capacity in a smaller package.
I've been meaning to get one of those CCTV batteries for a while, but so far the two RC batteries I have have been sufficient - I can get several hours of music out of one battery, but not particularly loud.
If it was my project, I'd get one of those CCTV batteries, mount it inside the speaker, and have a clever switching system (that I haven't quite worked out yet) that'll enable you to power the speaker from the wall or battery, or charge the battery.
You could use a wire link and two sockets on the back (one connected to the battery, one connected to the amplifier) so you can physically plug into either.
Hope this helps
Chris
If you want to use an SLA then things are easy
The amp can be designed as battery powered. That is the battery feeding via a switch to the amp.
The charger is connected across the battery with a diode in series to prevent the battery discharging back into the charger when mains power isn't present.
The rating of the charger can be such that it either powers the amp and can recharge the battery at the same time or it can be of lower current ability which means it would only charge the battery when the amp was not in use.
The charger needs to be able to supply around 15volts DC and be current limited. The diode will lose around 0.7 volts so the battery sees around 14.3 volts which is perfect.
The voltages for SLA's are important. The battery can stand 13.8 volts 24/7 but will take a longer time to come back to 100% charge after use. Up to 15 volts can be used for "cyclic" use where it is charged and discharged regularly and never left on charge for long periods.
Safety warning for SLA's You must always use an inline fuse connected as near as possible to the battery positive terminal. These batteries have a huge current capacity (even the small 7AH ones can just about start a small car) so the risk of fire if a short occured is an obvious danger.
The amp can be designed as battery powered. That is the battery feeding via a switch to the amp.
The charger is connected across the battery with a diode in series to prevent the battery discharging back into the charger when mains power isn't present.
The rating of the charger can be such that it either powers the amp and can recharge the battery at the same time or it can be of lower current ability which means it would only charge the battery when the amp was not in use.
The charger needs to be able to supply around 15volts DC and be current limited. The diode will lose around 0.7 volts so the battery sees around 14.3 volts which is perfect.
The voltages for SLA's are important. The battery can stand 13.8 volts 24/7 but will take a longer time to come back to 100% charge after use. Up to 15 volts can be used for "cyclic" use where it is charged and discharged regularly and never left on charge for long periods.
Safety warning for SLA's You must always use an inline fuse connected as near as possible to the battery positive terminal. These batteries have a huge current capacity (even the small 7AH ones can just about start a small car) so the risk of fire if a short occured is an obvious danger.
Be VERY careful if intending to use Li-on batteries. They need to be charged correctly or they WILL go bl00dy *BANG* - and quite spectacularly too!!! To do this, the chargers have some degree of intelligence and monitor the charging current and output voltage. Hence I would be cautious of adding a diode in series with the output of the charger as it may get confused due to the voltage drop caused by the diode.
Just a heads-up.
Andy
Just a heads-up.
Andy
Scary.... I think I will pass on the battery, lol.
Ok now I am brainstorming again.
I think it would be awesome to add an pod dock to the top of my enclosure. I am using a 12v 2a wall wart power supply. Is there enough amperage to power and charge the ipod?
Also thinking about adding a little clock that normally runs off of 1 AA battery but I would like to power it with the power supply as well.
Ok now I am brainstorming again.
I think it would be awesome to add an pod dock to the top of my enclosure. I am using a
12v 2a wall wart power supply. Is there enough amperage to power and charge the ipod? Also thinking about adding a little clock that normally runs off of 1 AA battery but I would like to power it with the power supply as well.
I don't do ipods
but aren't those things USB compatable ? If so they need 5 volts and no more than 500ma.
What happens to the clock when the unit isn't powered up... does it stop ?
Supply is easy... two series silicon diodes connected across where the AA battery goes. Stripy end to the negative terminal. These will function as a zener diode of a round 1.3 volts. A resistor feeds to the pos terminal from the 12 volt supply. Value around 6800 ohms at a wild guess.
If you add a "super cap" across the battery terminals and add a further diode in series with the resistor (to stop the cap discharging back into the PSU) it should allow the clock to run for quite some time with no AC power present.
Memory Backup Capacitors
but aren't those things USB compatable ? If so they need 5 volts and no more than 500ma.
What happens to the clock when the unit isn't powered up... does it stop ?
Supply is easy... two series silicon diodes connected across where the AA battery goes. Stripy end to the negative terminal. These will function as a zener diode of a round 1.3 volts. A resistor feeds to the pos terminal from the 12 volt supply. Value around 6800 ohms at a wild guess.
If you add a "super cap" across the battery terminals and add a further diode in series with the resistor (to stop the cap discharging back into the PSU) it should allow the clock to run for quite some time with no AC power present.
Memory Backup Capacitors
Batteries are okay, you just need to exercise some care. The fuse idea is always a good one. I haven't had a problem with mine yet.
For USB charging, search for USB car chargers. They convert 12v to 5v, and are often very cheap. Perfect for what you're after. You'll just need the USB lead to go from the charger to the iPod.
If you wanted a clock, I'd just put an AA battery in there. It'll last for ages, even during power cuts etc.
Chris
On a side note, if you do decide to go for batteries, make sure you use 8ohm speakers.
The battery will stand driving a pair of 4ohm speakers to full power, but the amplifier sure won't - it'll shut down because of over-current protection. Kinda irritating - the bass comes, and the song cuts off for a couple of seconds.
The drivers in my little speaker are 4ohm each, so caused the problem mentioned above.
I've wired them in series, added a PA driver in a small ported cabinet, and made a PLLXO.
Here's the result.
Chris
The battery will stand driving a pair of 4ohm speakers to full power, but the amplifier sure won't - it'll shut down because of over-current protection. Kinda irritating - the bass comes, and the song cuts off for a couple of seconds.
The drivers in my little speaker are 4ohm each, so caused the problem mentioned above.
I've wired them in series, added a PA driver in a small ported cabinet, and made a PLLXO.
Here's the result.
An externally hosted image should be here but it was not working when we last tested it.
Chris
The speaker wattage is the power it can handle safely. So a 10 watt amp on a 500 watt speaker is OK. A 2 watt amp on a 10 watt speaker is OK.
A practical point is that you shouldn't overdrive a low powered amp (so that it clips and sounds distorted) as that can damage speakers. conversely, a good speaker can usually handle an amp of considerably more power than the speaker is rated at as long as it isn't abused.
A practical point is that you shouldn't overdrive a low powered amp (so that it clips and sounds distorted) as that can damage speakers. conversely, a good speaker can usually handle an amp of considerably more power than the speaker is rated at as long as it isn't abused.
22 gauge is fine. Thats rated at around 7 amps. A lot depends on cable length as you want to minimise volt drop at high current.
I'm looking at this,
American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies and wire strength
I'm looking at this,
American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies and wire strength
That particular midbass driver is 130w RMS rated.
However, being a PA driver, it had a high resonance, meaning not much actual bass came out (struggled below 100Hz). I'm now using a HTiB "sub"woofer instead - more low end grunt, but the 3ohm load means the amplifier will shut down due to over-current occasionally.
PS - as Mooly said - the power the speaker will stand (without breaking) is irrelevant to the amplifier's point of view.
What is important is the speaker impedances you use - aim for about 8ohm at each channel for best results.
Hi guys!
Wanted to report back on these little amps. They are awesome! These little amps put out quite alot of sound with the right speaker and enclosure. I have made several little mp3 players for friends and family and they just love them.
I have a new question for all you wiring gurus. I recently came across these cute little Jewel LED's on ebay and was wondering if I can use it instead of the LED on the board.
4pcs Green Blue Red Yellow 12V LED DC Power Jewel Indicator Pilot Light Bulb | eBay
Of course I would desolder the LED on the board and wire new leads to the Jewel LED. That is of course if it will work. It is listed as a 12V LED. It doesn't say anything about milliamps or amps in the description. I am using a 2A 12V power supply.
I just think these LEDs would be so great on the outside of the enclosure.
Thanks in advance!
Wanted to report back on these little amps. They are awesome! These little amps put out quite alot of sound with the right speaker and enclosure. I have made several little mp3 players for friends and family and they just love them.
I have a new question for all you wiring gurus. I recently came across these cute little Jewel LED's on ebay and was wondering if I can use it instead of the LED on the board.
4pcs Green Blue Red Yellow 12V LED DC Power Jewel Indicator Pilot Light Bulb | eBay
Of course I would desolder the LED on the board and wire new leads to the Jewel LED. That is of course if it will work
. It is listed as a 12V LED. It doesn't say anything about milliamps or amps in the description. I am using a 2A 12V power supply.I just think these LEDs would be so great on the outside of the enclosure.
Thanks in advance!
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