# MFJ-550 Telegraph Straight Key for Morse Code — resale value

**MFJ-550 Telegraph Straight Key for Morse Code** sells for about **$52.94** new or sealed, based on real closed eBay sales.

## Value

| Condition | Value (USD) |
| --- | --- |
| New / Sealed | $52.94 |

Values are medians of real closed eBay sales, updated 2026-07-23. They are estimates for reference, not offers or appraisals — condition, completeness and edition move them a lot, so compare against the sold listings before pricing anything.

## Check the market

- [Sold listings on eBay](https://junkpal.ai/api/go?to=https%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_nkw%3DMFJ-550%2520Telegraph%2520Straight%2520Key%2520Morse%2520Code%26LH_Sold%3D1%26LH_Complete%3D1%26mkcid%3D1%26mkrid%3D711-53200-19255-0%26siteid%3D0%26campid%3D5339166094%26toolid%3D10001%26mkevt%3D1%26customid%3Dmd-sold&p=md-sold) — the closed sales these medians are computed from
- [Live listings on eBay](https://junkpal.ai/api/go?to=https%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_nkw%3DMFJ-550%2520Telegraph%2520Straight%2520Key%2520Morse%2520Code%26mkcid%3D1%26mkrid%3D711-53200-19255-0%26siteid%3D0%26campid%3D5339166094%26toolid%3D10001%26mkevt%3D1%26customid%3Dmd-live&p=md-live) — what sellers are asking right now

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## Details

| Field | Value |
| --- | --- |
| Brand | MFJ |
| Category | Car Electronics |

## About

The MFJ-550 is a Telegraph Straight Key designed for Morse Code operation, categorized under Car Electronics.

This key is sought after by Morse code enthusiasts and collectors interested in vintage or specialized communication equipment.

Resale value is influenced by the key's physical condition, whether it is complete with original parts, and any specific edition details.

## FAQ

**What is the MFJ-550?**

The MFJ-550 is a Telegraph Straight Key specifically designed for Morse Code operation.

**What factors affect the resale value of this key?**

Resale value is determined by the key's condition, completeness, and any specific edition it belongs to.

**Is this item categorized under car electronics?**

Yes, the MFJ-550 Telegraph Straight Key is categorized within Car Electronics.

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Full price guide: https://junkpal.ai/products/mfj-550-telegraph-straight-key-for-morse-code-b00ar0bgzq
How these values are computed: https://junkpal.ai/methodology
Cite as: "JunkPal price guide value as of 2026-07-23, based on real sold listings (junkpal.ai)"