The H@LF Project

[ThomasW]

This is a project cooperatively developed by Chasw98, JonMarsh, and myself.

H@LF stands for Help @ Low Frequencies

This box can replace the not so reliable CleanBox, as well as provide multiple other functions as discussed on the webpage.

We're currently in the beta testing phase, and expect the testing to be completed by the end of October.

There's a complete component list on the Mouser website (a link and password will be posted at the appropriate time.) To purchase all the components needed to 'stuff' the PCB, all one needs is the project name and password. Cost of the component parts is approx ~ $50 delivered

Note, the PCB is sold separately so it's not included in the $50.

There will be a presale (actually just a small deposit) for those wanting PCBs. PCB pricing will be announced once we have a feel for how many boards to be ordered to satisfy demand. The PCBs will be sold at cost + shipping, this isn't a for-profit undertaking

The adjustable controls (switches and pots) can be board mounted (seen in the pic below) or they can be placed on the chassis (an example of this is shown in Chasw98's hardwired prototype, seen in the link above).

A builders guide complete with pictures will be posted when the PCBs are available.

There will be several power supply options.

1) mounted inside a BFD (or similar device) and use it's power supply (CAVEAT: this is option is ONLY recommended for those knowledgeable in this kind of thing. If you blow up your electronics we're NOT responsible)
2) small breadboard device that augments a 'wall-wart' PC (this is the cheapest standalone option)
3) separate 'deluxe' supply. Available from places like Marchand Elec (see PS10-K or PS10-A)
4) so called 'surplus' (but new) supplies from some electronic supply houses. (these are very inexpensive but physically quite large.) One source is Skycraft Surplus

[chasw98]

There will also be a few different ways to build this.

One way will be to use 'hot rod' high end components. Namely a better grade of op amp. Good op amps cost about $0.50 each and work quite well. Audiophile or 'golden ear' op amps run about $5.00 each. There are 4 op amps in the project.

Another way to build the unit is by mounting it in your own or purchased enclosure and mounting the switches and potentiometers on the case for easy access to the controls. You would also want to mount the input/output connectors on the case also. This is nice because you can essentially mount all components including the power supply in one box and have regular audio connector cables hook to it, plug the power cord into the wall, etc.

I will make up bill of materials for the different options and they will be available to order easily at Mouser.

And ThomasW and I will be available to help with construction. It is actually quite easy if you know how to use a soldering iron.

Chuck

[txsmoke]

Looks very promising- I especially like the 6db boost for balanced out. Please keep us posted.

Mike

[dynamowhum]

Okay are you going to have a separate " I want a PCB " thread or can I just say give me one?

[ThomasW]

dynamowhum said:

Okay are you going to have a separate " I want a PCB " thread or can I just say give me one?

Hi,

There were 10 prototype boards made. These cost me $40ea since they were made by Advanced Circuits = VERY high quality. Several of these are going to beta testers.

If someone wants one of the $40 boards, I can make a very limited number at my cost.

After the beta testing phase, we'll have a sign-up for ordering boards done from a standard production run. The price will of course be much less than the $40ea proto boards.

There is no timeline for the production boards. At this point I'm swamped with projects for the RMAF 2007. After things mellow out in late October, I'll focus on organizing the buy of production boards. Right now there's simply no free time available for it....

[meier]

admin said:

There is no timeline for the production boards. At this point I'm swamped with projects for the RMAF 2007. After things mellow out in late October, I'll focus on organizing the buy of production boards. Right now there's simply no free time available for it....

Any news - or just feedback on the prototypes?

Regards
Thomas

[ThomasW]

meier said:

Any news - or just feedback on the prototypes?

3 people are currently building prototype boards. When they're done they'll post their findings.

[jman]

What will the final cost be like?

[chasw98]

Right now, you are looking at approx. $50 in parts plus the cost of the board. Depending upon what you use for the power supply, case, switches, lamps, etc. the price can change.

Chuck

[dustinb]

Any updates on this project?

[carvernut]

dustinb said:

Any updates on this project?

x2

[ThomasW]

dustinb said:

Any updates on this project?

Nope everyone having a board has been sidetracked building more important projects.

When I have info it will be posted.

[nhjeep]

Hi Thomas,

I would like to build the H@LF project - I'll breadboard it, then create my own PCB.

You mentioned that "There's a complete component list on the Mouser website (a link and password will be posted at the appropriate time.)" Would you be willing to share that with me so that I would be able to build a H@LF board.

I am completely aware that this is a BETA project currently under development. I would like to build the board for my own personal use.

Also, do you have a Gerber file for the PCB layout that you'd be willing to share?

Thanks in advance!

Jon Golubiewski

[ThomasW]

Hi,

I have a PCB available from the prototype run. Were there to be a production run there would be no changes. These are very nice boards made by Advanced Circuits, my cost was $40ea.

Sorry the Gerber files aren't available.

I tried to log-in at Mouser to check the files and was unable to do so. So I'm waiting to hear back from Chas as to what happened to the account.

[ThomasW]

I posting this to have it archived....

Here's a screen shot of the Mouser parts page. The "Ships Now" number is how many of that part are needed...

Mouser #: 887-1646P08-U
Mfr. #: 1646P08-U
Desc.: Balanced Line Drivers Balanced Audio Line Driver IC
Availability
1 Ships Now
$4.78 $4.78

Mouser #: 595-NE5532AP
Mfr. #: NE5532AP
Desc.: Amplifiers - Operational Dual Low Noise
Availability
4 Ships Now
$0.98 $3.92

Mouser #: 647-UPW1E560MDD
Mfr. #: UPW1E560MDD
Desc.: Low Impedance Radial Aluminum Electrolytic Capacitors - 105Degree 25V 56uF 5X15 20%Tol 2LS 105Deg
Availability
4 Ships Now
$0.31 $1.24

Mouser #: 581-BQ014D0823J
Mfr. #: BQ014D0823J--
Desc.: Boxed Metal Film Capacitors 0.082uF 63volt 5% Lead Free
Availability
4 Ships Now
$0.07 $0.28

Mouser #: 539-168104J100H-F
Mfr. #: 168104J100H-F
Desc.: DC Film Capacitors 100V .1uF 5%
Availability
11 Ships Now
$0.43 $4.73

Mouser #: 1055-TA1330-EVX
Mfr. #: 1055-TA1330-EVX
Desc.: Miniature Toggle Switches SPDT 3 PIN PC MNT
Availability
1 Ships Now
$2.44 $2.44

Mouser #: 1055-TA1360-EVX
Mfr. #: 1055-TA1360-EVX
Desc.: Miniature Toggle Switches DPDT 6 PIN PC MNT
Availability
2 Ships Now
$2.77 $5.54

Mouser #: 594-63P202T7
Mfr. #: M63P202KB30T607
Desc.: Single Turn Trimmers/Potentiometers 3/8 SQ 2Kohms 10% Single Turn, Cermet
Availability
1 Ships Now
$1.81 $1.81

Mouser #: 594-63P104T7
Mfr. #: M63P104KB30T607
Desc.: Single Turn Trimmers/Potentiometers 3/8 SQ 100Kohms 10% Single Turn, Cermet
Availability
1 Ships Now
$1.90 $1.90

Mouser #: 271-10K-RC
Mfr. #: 271-10K-RC
Desc.: 1/4W 1% Metal Film Resistors 10Kohms 1% 50PPM
Availability
3 Ships Now
$0.09 $0.27

Mouser #: 271-22K-RC
Mfr. #: 271-22K-RC
Desc.: 1/4W 1% Metal Film Resistors 22Kohms 1% 50PPM
Availability
3 Ships Now
$0.09 $0.27

Mouser #: 271-47K-RC
Mfr. #: 271-47K-RC
Desc.: 1/4W 1% Metal Film Resistors 47Kohms 1% 50PPM
Availability
1 Ships Now
$0.09 $0.09

Mouser #: 271-196K-RC
Mfr. #: 271-196K-RC
Desc.: 1/4W 1% Metal Film Resistors 196Kohms 1% 50PPM
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 271-162K-RC
Mfr. #: 271-162K-RC
Desc.: 1/4W 1% Metal Film Resistors 162Kohms 1% 50PPM
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 271-137K-RC
Mfr. #: 271-137K-RC
Desc.: 1/4W 1% Metal Film Resistors 137Kohms 1% 50PPM
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 271-121K
Mfr. #: 271-121K
Desc.: 1/4W 1% Metal Film Resistors USE 271-121K-RC
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 271-107K-RC
Mfr. #: 271-107K-RC
Desc.: 1/4W 1% Metal Film Resistors 107Kohms 1% 50PPM
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 271-97.6K-RC
Mfr. #: 271-97.6K-RC
Desc.: 1/4W 1% Metal Film Resistors 97.6Kohms 1% 50PPM
Availability
4 Ships Now
$0.09 $0.36

Mouser #: 575-113308
Mfr. #: 110-13-308-41-001000
Desc.: DIP Low Profile Sockets 8P GLD PIN GLD CONT
Availability
5 Ships Now
$0.78 $3.90

Mouser #: 535-08-600-10
Mfr. #: 08-600-10
Desc.: DIP/SIP Headers 8P FORK DIP HDR
Availability
6 Ships Now
$1.77 $10.62

Mouser #: 271-5.23K-RC
Mfr. #: 271-5.23K-RC
Desc.: 1/4W 1% Metal Film Resistors 5.23Kohms 1% 50PPM
Availability
1 Ships Now
$0.09 $0.09

Mouser #: 271-52.3K-RC
Mfr. #: 271-52.3K-RC
Desc.: 1/4W 1% Metal Film Resistors 52.3Kohms 1% 50PPM
Availability
1 Ships Now
$0.09 $0.09

Mouser #: 271-24.9K-RC
Mfr. #: 271-24.9K-RC
Desc.: 1/4W 1% Metal Film Resistors 24.9Kohms 1% 50PPM
Availability
7 Ships Now
$0.09 $0.63

Mouser #: 271-100-RC
Mfr. #: 271-100-RC
Desc.: 1/4W 1% Metal Film Resistors 100ohms 1% 50PPM
Availability
2 Ships Now
$0.09 $0.18

[nhjeep]

EXCELLENT! That will help A LOT!
Thanks for digging this up so quickly!

[ThomasW]

We just finished testing this power supply and it's extremely good. Impossible to beat the $10 price
www.skycraftsurplus.com/index.asp?PageAction=VIEWPROD&ProdID=1672

[nhjeep]

OK, I've placed my order!

Thanks for the list - and also the great tiip on the power supply.
I was simply going to build the Power supply,
but $10 for a MEDICAL GRADE Power supply is too sweet to pass by. Thx!


OK, Here's how to order (the QUICK way):

1. Goto http:\\mouser.com
2. Choose the Orange button on the right: "Import your Bill of Materials"
3. Log In (or create new account)
4. Cut & Paste the following text into the Text Field (Below "My Current Order")
5. Select the "Import BOM" button and Voila! You're all set to go!

MERCHANDISE TOTAL: $44.30 (7/31/08 in the U.S.)

Review your selections, Choose "Order Project X 1" (the items are in a project - not your shopping cart yet...), and you're on your way...

Note: Make sure you get everything you're going to need
Such as: a project box, case connectors (RCA, XLR and/or 1/4"),
Power Supply/or components to build one, etc...


Also: I've always had good experiences with Mouser. However, if you want to shop elsewhere, you can try http:\\newark.com or http:\\digikey.com I don't think they offer imporing a BOM, though...

Cheers!

Jon G.


|*****Cut and Paste From HERE*****
V

887-1646P08-U 1
595-NE5532AP 4
647-UPW1E560MDD 4
581-BQ014D0823J 4
539-168104J100H-F 11
1055-TA1330-EVX 1
1055-TA1360-EVX 2
594-63P202T7 1
594-63P104T7 1
271-10K-RC 3
271-22K-RC 3
271-47K-RC 1
271-196K-RC 4
271-162K-RC 4
271-137K-RC 4
271-121K 4
271-107K-RC 4
271-97.6K-RC 4
575-113308 5
535-08-600-10 6
271-5.23K-RC 1
271-52.3K-RC 1
271-24.9K-RC 7
271-100-RC 2

[nhjeep]

Hi,

The link that leads to Chasw98's write-up states:

"Frequency modules are 4 identical resistors soldered to a removable 8 pin DIP header The value of the resistors determines the Hi-Pass frequency. An Excel Spreadsheet will give users the ability to determine specific XO points."

I don't see anywhere where a default value of the resistors is called out. Does anyone have the spreadsheet - or at least a value to start with?

Thx!

Jon G.

[ThomasW]

Chas is going to send me the spreadsheet this PM. I'll upload it and post a link.