RCA 5751W1 vacuum tube - rare 5751 variant - black plates - new old stock - vintage Radio Corporation of America tube

Sold by LeedsRadio
+ $6.95 shipping

Only 1 available

+ $6.95 shipping
In stock
Preparation takes 1-2 business days
Arrives from the United States


Item details

New Old Stock RCA 5751W1, black plate vacuum tube. Original box is in fair condition. Tube is near mint - just a little branding wear. Pins are straight and clean. Perfect glass. Full getter. Tested on a Hickok 118A tube tester.

I often get asked what's the difference between a 12AX7 and a 5751.
The RCA HB3 (October 1953) says that the 5751 is a premium type "Intended for applications where dependable performance under shock and vibration are paramount."

While electrically similar they are not identical. The 5751 takes marginally higher filament power. If you look at the data sheets it seems that the 5751 has lower gm, but you have to watch out; The test conditions for the 12AX7A are Eb=250. Ec=-2, while 5751 are Eb 250, Ec=-3.

I calculated gm for both tubes from their respective graphs at Eb=250, Ec=-2
12AX7A = 1550 μmhos
5751 = 1500 μmhos

Not much of a difference at least at this operating point.

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Shipping & policies
Preparation takes 1-2 business days
Arrives from the United States
Estimated Shipping
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Zip or postal code

April 2018
Almost all orders received before 11 am will be shipped the same day.

Typical transit times:
Priority Mail: 3 business days
First Class Package: 4-5 business days

All items are shipped with tracking. You will receive an email with the tracking number once the item has shipped. Feel free to contact me at any time with questions.

If you need special packing for a gift or special occasion please let us know and we'll see what we can dream up.

I cannot ship under your UPS, DHL, or Fed Ex account.


We accept both PayPal and credit cards through Etsy's Direct Checkout.

You may cancel an order any time before it is shipped for a full refund.

Returns & exchanges
I gladly accept returns, exchanges, and cancellations
Contact me within: 5 days of delivery
Ship items back within: 7 days of delivery
Request a cancellation within: 1 hour of purchase
The following items can't be returned or exchanged
Because of the nature of these items, unless they arrive damaged or defective, I can't accept returns for:
  • Custom or personalized orders
  • Perishable products (like food or flowers)
  • Digital downloads
  • Intimate items (for health/hygiene reasons)
Conditions of return
Buyers are responsible for return shipping costs. If the item is not returned in its original condition, the buyer is responsible for any loss in value.
Questions about your order?
Please contact me if you have any problems with your order.
Additional return information
You can cancel an order any time before it has been shipped.

Preferential returns:
You can return any item that is not marked as "AS-IS" within seven (7) business days of receipt. Item must be in the condition it was shipped. You will receive a refund less the shipping cost to you. You must pay return shipping.

The one exception is digital downloads. There are NO returns on digital downloads.

I accept exchanges. You must pay shipping back to Leeds and shipping of new item to you.

Claims for damage:
Leeds has been shipping with the United States Postal Service for 18 years and shipped thousands and thousands of delicate electronic parts and fragile vacuum tubes. In that time we have had only ONE claim for damage.

In the extremely unlikely event that your item arrived damaged please contact me immediately. Save ALL packing.

If there is a problem please contact me through Etsy's convo system.
I want you to be happy.

I can ship international but please understand that USPS international rates are quite high.

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