Pearl Two

[exojam]

6L6,

Is this more of what you were referring to? Thanks.

CMF5547K000BER670 Vishay/Dale Metal Film Resistors

James

[6L6]

Originally Posted by exojam

6L6,
Is this more of what you were referring to?

I'm sorry, I was trying to be clever and it didn't come across in text...

In an extremely roundabout way I was trying to suggest that you don't bother changing the resistors. The Dale metal film that you have in there now are extremely good resistors, better than most. They are high tolerance and low noise.

$16 for one resistor doesn't seem like a logical place to spend money on a project like this. (My opinion.)

[exojam]

6L6,

I had not ordered the resistors for R20 as of yet so I do need to buy some.

I was planning on ordering them when I order the other two heatsinks.

James

[6L6]

Originally Posted by exojam

I had not ordered the resistors for R20 as of yet so I do need to buy some.

But you are using a 2M blue... 47K is the recommended load an it is there in the 47k resistor right before the first gain stage. You won't need anything in r20 with that cart.

R20 is used if you need to adjust the load to something else than 47K

[exojam]

6L6,

Now I see. Is that R19 you are referring to? Thanks.

James

[6L6]

Yes. R19 is your loading resistor. R20 adjusts it.

[exojam]

Very good. Thank you again.

James

[exojam]

Well I pretty much got most of everything else soldered on today. I did take out R19 since I had a 47.5K ohm in there and will replace it with a straight 47K. That may not be necessary but I am going there anyway.

I also found that even after my double checking my parts I did not have C7 so I will have to order that. I will also need to find the red leds.

Next stop is to try and find the housing I will want to use. I am hoping to get my B1 in with the Pearl boards, possibly even the power supply.

I also need to get a nut and bolt for the heat sink. I took them to the hardware store yesterday and got some that fit it but found out they are to large for the voltage reg devices.

James

[exojam]

Would either of the below transformers work for this application?

The Plitron is the one I show listed in the parts spreadsheet I have but I would like to know if the Antekic would work work since it is about 60 dollars less. Thanks.

Plitron 30 VA - 2 x 115 V @ 50/60 Hz (17017201 - 30 + 30 V at 0.5 A)

Antek - AN-0532
Outputs 2x, Power 50VA, Output Voltage 32, Current .8a

James

[6L6]

Why do you want 32v secondaries? That will lead to ~44v rectified, which will need to get knocked down to a minimum of 40v (maybe 35v depending on the brand of 7824/7924) at the regulator inputs, and then regulated all the way down to 24v by the regulators. I only used a transformer with 30v secondaries because I had it on hand.

If you are buying the transformer just get this one - http://www.antekinc.com/details.php?p=647

It's shielded and should be quiet. It's also less than 18 bucks.

Then buy the "PS-KIT" from chipamp.com - Order | Chipamp.com

With the addition of a big diode bridge like this - GBPC3502-E4/51 Vishay Semiconductors Bridge Rectifiers you will be able to build the power supply just like the one shown in the original article.




Another member (budwiser) made one with this setup and it's perfect for this project --




If you look here (post #1387) you will see a great implementation. (yes, you need to click on the links to see the photos)

Pearl Two


Lastly, you need heatsinks for your regulators.