Partial Silver Transformers
Single-Ended Output Transformers
- Single secondary SE output transformers available with primary and secondary impedances of your choice (within reasonable working values).
- Bandwidth will exceed -1db 25Hz to 20 khz+ on all models.
- Silver wire windings available at current market prices.
- Designs to 100 watts.
- Parafeed designs.
- High voltage designs.
SE Output Transformer Selection Guide
1. Primary impedance (commonly used) needed, select one: 1K, 1.5K, 2K, 2.5K, 3K, 3.5K, 4K, 4.5K, 5K, 6K, 7K, 8K, 9K,10K.
2. Primary current (max based on 25Hz saturation), select one: 20ma., 40ma., 50ma., 65ma., 80ma., 100ma., 120ma., 150ma., 200ma., 250ma., 300ma.
3. Power level maximum, select one: 3w, 5w, 10w, 15w, 20w, 30w, 40w, 50w, 75w, 100w.
4. Secondary impedance (single) in ohms, select one: 4 - 6 - 8 - 12 - 16 - 32 (6 ohms is for 4 and 8 and 12 ohms is for 8-16) or others can be made.
OR
Multiple tap secondary impedances, select one combination: 4-8; 8-16; 4-8-16 etc.
5. Secondary wire type: C - copper,PS - partial silver, S - solid silver.
PS can be used only for single secondary transformers.
Order Examples:
3K, 100ma., 15w, 8 ohms, C for 300B tube $165.00 each
5K, 50ma., 3w, 16 ohms, C for 45 tube $95.00 each
3K, 65ma., 5w, 4-8 ohms, S for 2A3 tube silver market price
5K, 100ma., 20w, 8 ohms, C for 845 tube $165.00 each
5K, 80ma., 10w, 12 ohms PS for 50 tube $238.00 each
1.5k, 200ma., 20w, 4 ohms PS for 2 X 300B’s $484.00 each
9K, 100ma., 20w, 6 ohms, C for 211 tube $165.00 each
3K, 200ma., 45w, 4,8 ohms, C for 2 X 845’s $356.25 each
Prices (based on core size and secondary arrangement
| Primary Current | Single Sec Copper | Single Sec. PS | Multiple Tap Copper |
|---|---|---|---|
| 20ma | $75.00 | $127.50 | $93.75 |
| 40ma | $85.00 | $144.50 | $106.25 |
| 50ma | $95.00 | $161.50 | $118.75 |
| 65ma | $105.00 | $178.50 | $131.25 |
| 80ma | $140.00 | $238.00 | $175.00 |
| 100ma | $165.00 | $280.50 | $206.25 |
| 120ma | $185.00 | $314.50 | $231.25 |
| 150ma | $205.00 | $348.50 | $256.25 |
| 200ma | $285.00 | $484.50 | $356.25 |
| 250ma | $370.00 | $629.50 | $462.50 |
| 300ma | $450.00 | $765.50 | $56.50 |
- Impedance of primary
- Current through primary
- Expected power output
- Impedance of secondary(s)
Single Ended Output Transformer Hook-Up Information For Our Older Original Designs
SPECIFIC INSTRUCTIONS FOR INSTALLATION
Output impedances are selected by interconnecting the eight tagged secondary leads as shown below:
| 16 Ohms | 8 Ohms | 4 Ohms | 2 Ohms |
|---|---|---|---|
| S4 Out | S4 Out | Join S1, S4 Out | Join S1, S2, S3, S4 Out |
| Join S1, F2 | Join S1, F2, F3 | Join S2, S3, F1, F4 | Join F1, F2, F3, F4 Out |
| Join S2, F3 | Join S2, S3, F4 | Join F2, F3 Out | |
| Join S3, F4 | F1 Out | ||
| F1 Out |
- Use standard electrical wire nuts or solder to join leads.
- Do not pull sleeving off of lead.
- Do not attempt to remove screws that are holding the transformer together. This can reduce the low frequency response.
- Do not strike laminations with any heavy objects. This will disorient the lamination material.
- Do not pull or hold up transformer with its leads.
- Do not operate transformer without a proper load (speaker or power resistor) with a signal into the amplifier. This will cause the signal to be at a very high voltage due to the infinite impedance and will arc across to the secondary. This will destroy the transformer.
- Do not exceed primary current rating. This will heat transformer and saturate the core causing distortion of low frequencies.
- Do not install power transformer and chokes in magnetic proximity of the output transformer. This will cause hum in the speaker.
- Always ground one side of the secondary for safety.
- Always connect BLUE or VIOLET wire to the plate of the tube. This will assure maximum bandwidth to the lower capacity at that end of the primary.
- The B+ lead can be RED, ORANGE or WHITE depending on the model of the transformer.