MiniMAX BOM

[1]

These are the power decoupling caps. A good quality power cap is all that's necessary. 680uf seems to be the smallest necessary to prevent power startup stuttering in the standard configuration.

[2]

These are optional bypass caps for the output coupling electrolytics. A good film cap will increase the sound quality over the electrolytics alone, especially in the highs. 0.1uf to 0.22uf is a suggested size. Caution: film cap bypassing is not "scientifically" predictable in all cases. Deviation from known combinations may yield unpredictable results.

[3]

These are the output coupling caps. Their size is directly related to the cutoff frequency seen by the headphones. 470uf is sufficient down to 32 ohm headphones. Audio-quality is desired, but power caps will work well with film cap bypassing.

[4]

This is a new audio-quality Nichicon at Mouser.

[5]

[6]

Cathode bypass cap. These are optional, but may increase plate resistance, a good thing. A bipolar cap would probably be best, here - if you use one.

[7]

This should also be a signal-quality cap. A Nichicon Muse ES would be a great choice here (Handmade Electronics or Beezar.com)

[8]

1/2W size, 10.8mm maximum, but either 1/4W or RN55/RN60 sizes will work.

[9]

1/2W size, 10.8mm maximum, but either 1/4W or RN55/RN60 sizes will work.

[10]

1/2W size, 10.8mm maximum, but either 1/4W or RN55/RN60 sizes will work.

[11]

These are optional grid resistors for the tubes, usually used to quell tube oscillations. Not found to be needed in the SSMH, they won't hurt, either - install 470 - 1K ohms if you wish.
1/2W size, 10.8mm maximum, but either1/4W or RN55/RN60 sizes will work.

[12]

These are the pot input resistors, used to "push" the pot into a greater adjustment range for volume. Size for a rating equal to the pot's impedance as a starting point. 7.5mm lead spacing, 1/4W or V-D RN55 size, maximum.

[13]

Use these if you want low gain for low-impedance efficient phones.

[14]

50K is suggested, but 100K or 10K will work just fine, too. If you use R16 and R17, be sure to adjust their size according to the pot rating you select. For instance, for a 10K pot, use 10K for R16/R17. For a 100K pot, use 100K for R16/R17, and so on.

[15]

[16]

Also available at Beezar.com

[17]

This resistor is sized for a single 10ma load.
This resistor is sized to use two LED's under the tubes. The resulting current should be about 10ma for each resistor, plenty for super-bright LED's. NOTE: this resistor will need to be installed in tombstone or kneeling fashion.
If you want a panel LED, too - install a separate resistor in the leads for the panel LED; feed it directly from the power terminal block.

[18]

LED's are plentiful. Simply select the highest-rated MCD LED that uses 20ma current and is a T1, 3mm LED.

[19]

Mouser Part #
604-WP7104PBC/H
is 3600mcd for $1.97

$tarving $tudent Millett Hybrid			PCB Design/Layout by Dsavitsk				Last revised: 7/4/18	BOM by Tom Blanchard
PART ID	DESCRIPTION	QTY	SOURCE	PART NO	EACH	TOTAL	SOURCE	PART NO	EACH	TOTAL

Please read the comments! (little red triangles in the upper right corners)

BASIC CIRCUIT
Please note - the caps are limited to 20mm height if the "L" case is used.
C1/C6	680uf 63V Electrolytic (18mm dia max)[1]	2	Mouser	647-UPW1J681MHD3	$0.97	$ 1.94	DigiKey	P11276-ND	$ 1.69	$ 3.38
C2/C4	0.1uf/0.22uf 250V Film Cap (10 or 15mm ls)[2]	2	Mouser	505-M10.22/250/10	$1.11	$ 2.22	DigiKey	BC1609-ND	$ 1.25	$ 2.50
C3/C5	470uf 63V Electrolytic (18mm dia max)[3]	2	Mouser	647-UKW1J471MHD[4]	$1.02	$ 2.04	DigiKey	P10352-ND	$ 1.36	$ 2.72
C3a/C5a*	0.1uf/0.22uf 250V Film Cap (10 or 15mm ls)[5]	2	Mouser	505-M10.22/250/10	$1.11	$ 2.22	DigiKey	BC1609-ND	$ 1.25	$ 2.50
C7/C8*	220uf 16V Nichicon Muse ES[6]	2	Beezar.com	Muse ES, 220uf 16V[7]	$1.00	$ 2.00	Beezar.com	Muse ES, 220uf 16V	$ 1.00	$ 2.00


R1/R7	33K ohm[8]	2	Mouser	71-RN55D-F-33K	$0.16	$ 0.32	DigiKey	CF1/433KJRCT-ND	$ 0.20	$ 0.40
R2/R8, R4/R10	220K ohm[9]	4	Mouser	71-RN55D-F-220K	$0.16	$ 0.64	DigiKey	CF1/4240KJRCT-ND	$ 0.20	$ 0.80
R3/R9, R5/R11, R6/R12, R13	2K ohm[10]	7	Mouser	71-RN55D-F-2.0K	$0.16	$ 1.12	DigiKey	CF1/42KJRCT-ND	$ 0.20	$ 1.40
R14/R15*	1K ohm[11]	2	Mouser	71-RN55D-F-1.0K	$0.10	$ 0.20	DigiKey	CF1/41KJRCT-ND	$ 0.20	$ 0.40
R16/R17*	50K ohm [12]	2	Mouser	71-RN55D5102F	$0.16	$ 0.32	DigiKey	CMF49.9KQFCT-ND	$ 0.29	$ 0.58
R16R17* - low gain	100K ohm[13]	2	Mouser	71-RN55D-F-100K	$0.16	$ 0.32	DigiKey	CMF100KQFCT-ND	$ 0.29	$ 0.58


RV1 (please read comments)[14]	Alpha 50K Audio Taper Stereo Pot RV122F-20-15F-A10K[15]	1	Mouser	313-1240F-50K	$3.16	$ 3.16	DigiKey	N/A		$ -
Q1/Q2	MOSFET, IRF510, TO-220 case	2	Mouser	844-IRF510PBF	$0.96	$ 1.92	DigiKey	IRF510PBF-ND	$ 0.96	$ 1.92
Tubes**	19J6	2	Beezar.com	19J6	$10.00	$ 20.00	Beezar.com	19J6	$ 10.00	$ 20.00
Tubes Tested/Matched within 10%	Per tube, two triodes each	2	Beezar.com	Testing/Matching	$2.00	$ 4.00	Beezar.com	Testing/Matching	$ 2.00	$ 4.00


MISC:
Headphone Jack	Neutrik NMJ6HCD2	1	Mouser	550-22302[16]	$1.46	$ 1.46	DigiKey	N/A		$ -
RCA jacks	HiQ gold-plated copper, 1 pair	1	Beezar.com	RCA-Nyl	$4.00	$ 4.00	Beezar.com	RCA-Nyl	$ 4.00	$ 4.00
Tube Socket	7-pin PCB Ceramic, tin-plated	2	Beezar.com	GZC7-Y-T	$2.00	$ 4.00	Beezar.com	GZC7-Y-T	$ 2.00	$ 4.00
Terminal Block, 3-pos	5mm (or 5.08mm)	1	Mouser	571-2828363	$0.45	$ 0.45	DigiKey	ED1931-ND	$ 0.93	$ 0.93
Terminal Block, 4-pos	5mm (or 5.08mm)	2	Mouser	571-2828364	$1.18	$ 2.36	DigiKey	ED1930-ND	$ 0.62	$ 1.24
Standoff Kit, for 3rd slot	SSHM Standoff kit, screws, etc.	1	Beezar.com	SSMH Standoff Kit	$2.00	$ 2.00	Beezar.com	SSMH Standoff Kit	$ 2.00	$ 2.00
SSMH PCB Heat Sink Kit	Bergquist pad, shldr washer, screws, etc.	2	Beezar.com	Heat Sink Kit	$4.00	$ 8.00	Beezar.com	Heat Sink Kit	$ 4.00	$ 8.00
Heat Sink	TO-3 style, Aavid #569003B00000G	2	Mouser	532-569003B00	$2.71	$ 5.42	DigiKey	HS110-3-ND	$ 2.56	$ 5.12
Knob	Silver anodized Al, 1.25" dia, 1/4" shaft	1	Mouser	450-6007	$3.22	$ 3.22	DigiKey	KN1251B1/4-ND	$ 12.83	$ 12.83

RLED***	2.4K, 2W metal oxide resistor[17]	1	Mouser	282-2.4K-RC	$0.19	$ 0.19	DigiKey	P2.4KW-2BK-ND	$ 0.28	$ 0.28
LEDL/R	Tube LED's, 3mm 5000 mcd - Blue[18]	2	Beezar.com	SuperBrite 3mm LED[19]	$0.25	$ 0.50	Various	754-1248-ND	$ 0.42	$ 0.84

PCB	Circuit Board	1	Beezar.com	SSMH PCB	$15.00	$ 15.00	Beezar.com	SSMH PCB	$ 15.00	$ 15.00


POWER SUPPLY
Power Supply	120/240V, 48VDC@0.38A, w/power cord	1	Various	Cisco PSA-18U	$15.00	$ 15.00	Various	Cisco PSA-18U	$ 15.00	$ 15.00
Power Socket	2.5mm Metal Socket, 100VDC 2A	1	Mouser	163-4025	$3.52	$ 3.52	Radio Shack	274-1576	$ 3.49	$ 3.49
SPST Switch	Black Rocker w/round hole & thread	1	Mouser	103-R13-135A-02-EV	$1.41	$ 1.41	Radio Shack	275-693	$ 2.79	$ 2.79


ENCLOSURE***
PCB: approx. 4" x 3"	Hammond 1455N1201 - Black	1	Hammond	1455N1201BK	$21.37	$ 21.37	Hammond	1455N1201BK	$ 21.27	$ 21.27
	Machining, tube holes, heat sink mounts, and all endplate openings	1	Hammond	Hammond machining ($50 total per case)	$23.73	$ 23.73	Hammond	Hammond machining ($50 total per case)	$ 23.73	$ 23.73
				TOTAL		$154.05		TOTAL		$ 163.70
								(not all parts available)
* Optional parts - Dsavitsk additions over Pete Millett original
** 19J6 tubes at Beezar.com to be sold in tested pairs with kits, only
*** The LED resistor is treated as a single source to two Tube Light LED's. If you choose to use a panel LED, either by itself or with the Tube LED's, you will need to calculate your own resistor sizes. We do not recommend feeding three LED's from this resistor.