Output-Single Ended-Ultra Linear

Key Features

• "Over designed" for high fidelity, single ended, Class-A, tube output circuits (triode, tetrode or pentode tubes).
• Enclosed (shielded), four slot, chassis Type "X" mounting.
• Frequency response at least 20 Hz. to 20 Khz. at full rated power (+/- 1 db max., ref. 1 Khz.)
• Insulated flexible leads 8" min.
• For maximum versatility, all units (except the 1642SE & 1638SEA) include a 40% screen tap for Ultra-Linear, tetrode/pentode operation (if desired). The 1642SE & 1638SEA do NOT include this screen tap as they were designed principally for high impedance triode tubes.
• High quality laminations, (M6) grain oriented silicon steel.
• Core is gapped to reduce core saturation in Class-A tube amplifier circuits.

Part Number (click for price and to order)	Audio Watts	Primary			Ultra-Linear 40% Primary Tap	Secondary Impedance (Ohms)	Hipot Test (VRMS)	Data Sheet Reader File	Weight (lbs.)
		Impedance (Ohms)	Max. DC Bias	Inductance
1640SEA	30	1,250	200 ma.	14 Henrys	Yes	4-8-16	2,000		11
1627SEA	30	2,500	160 ma.	20 Henrys	Yes	4-8-16	2,000		11
1630SEA	30	3,500	135 ma.	42 Henrys	Yes	4-8-16	2,000		11
1628SEA	30	5,000	120 ma.	48 Henrys	Yes	4-8-16	2,000		11
1642SE	75	5,000	300 ma.	53 Henrys	No	4-8-16	3,500		28
1629SEA	30	6,500	100 ma.	55 Henrys	Yes	4-8-16	2,000		11
1638SEA	30	10,000	90 ma.	88 Henrys	No	4-8-16	2,000		11

Suggested Tube Types

Notes: The above examples of possible combinations are to help you narrow down the choices of transformers for your favorite tube types. How you operate the tubes (ultra-linear, bias, plate voltage, operating points, etc.) will change optimum plate load impedance. Only a few of the most popular tubes are shown. A tube manual or tube manufacturer's technical data sheets should be consulted first, before making a decision on a proper output transformer

Mechanical Data

Schematic & Hook Up Data

Notes: - RED wire connects to B+ - BLUE/YELLOW wire connects to screen (optional use) - BLUE wire connects to the tube plate - The 1642SE & 1638SEA do not include a primary screen tap (as they are designed for triode applications).