Transformer - Output, 8 W, Single Ended

Transformer - Output, 8 W, Single Ended

Transformer - Output, 8 W, Single Ended image 1
Transformer - Output, 8 W, Single Ended image 2
Transformer - Output, 8 W, Single Ended image 3
Customer image:<br/>"AK Dave Gillespie DGSE-1"
Customer image:<br/>"New transformer in Motorola 397"
Customer image:<br/>"2 OPT’s in an old Tube amp"
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Transformer - Output, 8 W, Single Ended image 1Transformer - Output, 8 W, Single Ended image 2Transformer - Output, 8 W, Single Ended image 3
Customer Images:
Customer image: "AK Dave Gillespie DGSE-1"Customer image: "New transformer in Motorola 397"Customer image: "2 OPT’s in an old Tube amp"
$15.50
In Stock

Specifications

Power 8 W
Primary Impedance 5,000 Ω single-ended
Secondary Impedance 8 Ω
Primary DC Resistance (Red to Blue) 230 Ω
Mounting Centers 2.375"
Mounting Type U-bracket
Weight 0.7 lbs

Wiring:

Wiring
SKU:
P-T31
Item ID:
003561
RoHS Compliant
Product Measurements by Type
Item Height1.606 in.
Item Length2.8 in.
Item Width1.9 in.
Mounting Hole Center to Center A2.35 in.
Mounting Hole Diameter0.187 in.
Mounting TypeU-bracket
Power8 W
Primary D.C. Resistance, blue-red230 Ω
Primary Impedance5 kΩ
Secondary Impedance8 Ω
Packaging Information
Packaging Dimensions2.8 in. × 1.6 in. × 1.8 in.
Weight (Packaging)0.676 lbs.
GIF: WiringAll Models

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Specifications, Files, and Documents

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Questions and Answers

Click each question to see its answers.
Asked by Anonymous on February 22nd, 2017.
Matt H.
February 23rd, 2017
Staff Member
The maximum DC bias depends on the tube being used, the plate voltage, and the value of the cathode resistor.
Anonymous
April 17th, 2018
I think this question was not referring to tube bias, but maximum DC a single-ended transformer was designed for (or is recommended). That is a common spec from transformer manufacturers and should be observed to avoid core saturation. It's much less of a concern for push-pull because it's normally balanced or can be adjusted to be. Thanks
Anonymous
April 17th, 2018
Let's read between the lines, in case there is no published spec (available) from the manufacturer. The transformer is recommended for 6V6, 7C5 and 6BQ5. The 7C5 is the Loctal socket version of 6V6, so let's say there are only two tubes we know are suitable. I found one version of Fender Champ schematic that had a cathode voltage of 19 VDC with a 470 ohms cathode resistor. 19/470 = 0.04A = 40 mA. 2nd example I looked up was for a 6BQ5/EL84 SE amp with 7.7 VDC cathode voltage and a 150 ohm cathode resistor. 7.7/150 = 0.051A = 51 mA. Those may not maximum allowable, but based on the recommended tubes and mostly satisfied users we can assume 51 mA DC is OK.
Asked by Anonymous on April 2nd, 2016.
JustinG
April 5th, 2016
Staff Member
Top Contributor
Most of our current transformer stock will be leaning towards guitar amplification. I would suggest checking out the Hammond offerings as those would have the best chance of meeting your needs.
Anonymous
December 24th, 2016
Look at the offerings from One Electron.
Asked by Anonymous on June 30th, 2016.
Matt H.
June 30th, 2016
Staff Member
By looking at the spec sheet above, this transformer should work with 6V6, 7C5, and 6AQ5/A tubes.
Anonymous
March 3rd, 2021
It worked with my 6V6 output tube guitar amp.
Asked by Anonymous on April 18th, 2016.
JustinG
April 19th, 2016
Staff Member
Top Contributor
From what I can see you would want to use an 8 ohm speaker with this transformer.
Asked by Anonymous on April 29th, 2016.
JustinG
April 29th, 2016
Staff Member
Top Contributor
The distance between mounting holes is 2-3/8".
Asked by Anonymous on June 30th, 2016.
Matt H.
December 16th, 2016
Staff Member
Both a 6V6 and a 6J5 tube have 8 pins each. If you are asking how many used or active pins, the answer is different. A 6V6 is a pentode. A 6J5 is a triode.
Asked by Anonymous on September 13th, 2016.
Matt H.
September 14th, 2016
Staff Member
Yes, this transformer should work with the El84. We use this transformer with our MOD102 Kit: K-MOD102.
Asked by Anonymous on October 22nd, 2016.
Matt H.
October 26th, 2016
Staff Member
Hello, this transformer should work with EL84 tubes.
Asked by Anonymous on October 23rd, 2016.
Matt H.
October 26th, 2016
Staff Member
Hi, this is a current production transformer.
Asked by Anonymous on November 20th, 2017.
Matt H.
November 20th, 2017
Staff Member
These are made in Mexico.
Asked by samlcompton on November 20th, 2018.
BradWbr
November 21st, 2018
Staff Member
Asked by Anonymous on January 10th, 2020.
Anonymous
May 18th, 2021
Yes this will work with 6F6. They are very identical tubes
Asked by Anonymous on April 16th, 2020.
MikeT
April 17th, 2020
Staff Member
We would only recommend using this with a matching 8 ohm load.
Asked by Anonymous on January 9th, 2021.
MikeT
January 15th, 2021
Staff Member
The power transformer should be determined using the full circuit since different tubes and choices like the rectifier type will need specific voltages from the power transformer.
Asked by Anonymous on January 24th, 2021.
MikeT
January 27th, 2021
Staff Member
Since it is only rated at 8W, this would not be a great choice for an EL34.

Product Reviews

4.94 out of 5 based on 32 reviews
- July 10th, 2021
5 out of 5

Excellent quality great product!

- April 14th, 2021
5 out of 5

Restoring a 1941 Zenith 7s529 radio. The audio output transformer was “open.” Took a chance and bought the PT 31 transformer. Installed the new transformer and the radio came back to life!! The mounting holes do not line up. Made up my own bracket and good to go! Highly recommend this transformer!!

- March 20th, 2021
5 out of 5

I have used a bunch of these transformers in a number of single ended audio amplifiers using a variety of final output tubes including the 6F6, 6V6, 6L6 and 12BH7. Projects include a 1939 vintage regenerative receiver, single ended stereo amplifiers and a stereo headphone amp. Testing with a signal generator and an oscilloscope yields a flat response from about 100 Hz up to 20kHz. The roll off is gradual down to about 20Hz. Since my speakers [big Pioneer CS-V9910's] roll off at about 40Hz, these are are ideal , especially for the price. As long as I keep building low-power audio amplifiers, I'll keep using these.

- March 1st, 2021
5 out of 5

I was rebuilding a small antique guitar amp from the early ‘50s, and found that they had substituted the case and thus the speaker, and thus the output xformer (because it was mounted to the speaker in this amp). I wondered if a different transformer would make a difference in the sound output level. The power tube is a single ended 6V6. Others indicated that this transformer should work for a 6V6, so I ordered it. I’m happy to say it works very well with my 6V6 circuit, with no modifications necessary. This xformer had a different primary winding resistance than the one that has been substituted. Since it did boost the output volume a bit, I think the 6v6 output tube had been trying to feed a mismatched transformer.

- January 14th, 2021
5 out of 5

Since repairing old tube radios is just a wintertime hobby, I do not like to get much invested in it. I found this transformer to be a cost effective replacement for most of the 30s and early 40s radios. Performance is great.

- October 28th, 2020
5 out of 5

This output transformer worked fine on a Majestic 1770 with a single 6K6 output tube.

- September 2nd, 2020
5 out of 5

Perfect for single ended el84. Dave Gillespie spec'd this into the Magnavox 8600 "flea amp" project (AudioKarma)

- April 28th, 2020
5 out of 5

The perfect replacement and value for my HeathKit Mohawk RX-1 receiver!

- November 24th, 2019
5 out of 5

top

- November 1st, 2019
5 out of 5

Excellent supply of products & excellent service.