Has anyone tried this schematic from the Beavis HiFi site? It's part of his Kitchen Sink Phono Stage and I was wondering if it would be a good match for my Hagerman Bugle phono preamp. The Bugle runs fine on 2 9v batteries but this schematic looks interesting.
It's unverified and Dano is MIA.
It's unverified and Dano is MIA.
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Change all resistors to 10k. This will give lower noise and also save the LED.
Unless you are running off a battery, then you can keep the 220k resistors.
The 220uF capacitors at the output of the buffer are somewhat counter-productive. Rather increase the capacitance at the input side and let the buffer do its job.
Unless you are running off a battery, then you can keep the 220k resistors.
The 220uF capacitors at the output of the buffer are somewhat counter-productive. Rather increase the capacitance at the input side and let the buffer do its job.
Why not just use Hagerman's Power supply for the Bugle? It's probably more expensive, but a real ground always beats a virtual one, which is what you are creating with the BUF634.
Hagerman's power supply is fine but above my budget right now. The dual 9 volts do the job well enough for many Bugle users but I am intrigued with the idea of no batteries or traditional high voltage power supply.
Tangent has a really good writeup on virtual ground circuits here: Virtual Ground Circuits. The BUF634 circuit is mentioned(in a simplified form), along with several interesting alternatives. Regardless of the circuit, you will have to get a 24V(ish) DC wallwart to provide the source power, http://www.ebay.com/itm/BRAND-NEW-2...841?pt=LH_DefaultDomain_0&hash=item3cbb21abe1 if you're not afraid of a switching supply..
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Hey thanks, MrSlim and discrete ! At the very least, it can provide some feedback on the pros and cons of this particular method. I'll post my results once my parts arrive and I get her up and running.
I used basically the same circuit (which is shown in the LM675 datasheet at national.com), but with 35V in and an LM1875 in place of the BUF634. It worked very well for current up to about 1.5 Amps (which I happened to limit it to, in that case)
But why not just get two 12V wall adapters and connect the negative of one to the positive of the other? That connection would be your "ground", and the remaining positive and negative leads would be +12 and -12.
You have to make sure that you get the right type of wall adapters, for that. They have to be the common isolated type. I think that in the USA they would say "Type 1" on them, but can't quite be sure of that.
There is more information, here: Notes on the Troubleshooting and Repair of AC Adapters, Power Supplies, and Battery Packs, and Other Related Information
You could also add protection diodes (see the link above).
And you could add linear regulators.
Tom
But why not just get two 12V wall adapters and connect the negative of one to the positive of the other? That connection would be your "ground", and the remaining positive and negative leads would be +12 and -12.
You have to make sure that you get the right type of wall adapters, for that. They have to be the common isolated type. I think that in the USA they would say "Type 1" on them, but can't quite be sure of that.
There is more information, here: Notes on the Troubleshooting and Repair of AC Adapters, Power Supplies, and Battery Packs, and Other Related Information
You could also add protection diodes (see the link above).
And you could add linear regulators.
Tom
Got my parts and I'm near completion. Just troubleshooting my panel mount 2.1 dc power jack - I get those pins goofed up rather often!
I'll post my findings hopefully this weekend if time permits.
And thanks gootee, that link is very useful for reference!
I'll post my findings hopefully this weekend if time permits.
And thanks gootee, that link is very useful for reference!
"We have Wormsign!"
Translation: The Kitchen Sink BUF 634 power supply (with modifications) is quite operational. Needs more testing ( my pioneer pl4 TT is acting touching, so while I have clear audio, it's slowwww due to a rotor issue).
Good news is nothing has blown up, no hiss or hum that I am aware of, and was a pretty easy build. I followed discrete's tips to the best of my ignorant capabilities: resistors are all 10k and I removed the 220 caps on the output. The input caps have been beefed up with 3 330uF caps in parallel (what I had available).
More testing needs to be done but so far, I feel this is a worthy candidate for a Bugle power supply. I'm sure there's something I'm not doing "right", but this alternative cost me around 25 to 30 bucks; a pretty good savings in my book. More later...
Translation: The Kitchen Sink BUF 634 power supply (with modifications) is quite operational. Needs more testing ( my pioneer pl4 TT is acting touching, so while I have clear audio, it's slowwww due to a rotor issue).
Good news is nothing has blown up, no hiss or hum that I am aware of, and was a pretty easy build. I followed discrete's tips to the best of my ignorant capabilities: resistors are all 10k and I removed the 220 caps on the output. The input caps have been beefed up with 3 330uF caps in parallel (what I had available).
More testing needs to be done but so far, I feel this is a worthy candidate for a Bugle power supply. I'm sure there's something I'm not doing "right", but this alternative cost me around 25 to 30 bucks; a pretty good savings in my book. More later...
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