ERA User Guide

Signing transactions

Sign a Bitcoin transaction

You will haveYou have checked and signed a Bitcoin PSBT (an unsigned Bitcoin transaction) on ERA and handed it back to your software wallet.
Time5 min
You needERA device, a linked Bitcoin software wallet

This example sends 0.0006 BTC from a wallet imported from the standard test phrase abandon × 11 about. Your amounts and addresses will differ; the screens are the same.

Steps

Part 1: Scan the request

  1. In your software wallet, create the send and choose to sign it with ERA.

    Image coming soon — phone app (for example Sparrow, BlueWallet or Nunchuk) showing the animated PSBT QR code

  2. On ERA, on the wallet page, tap SIGN — or tap SCAN QR on the Main menu; ERA picks the wallet for you.

    Wallet page with SIGN and DEPOSIT buttons
    Wallet page with SIGN and DEPOSIT buttons
Starting from SCAN QR on the Main menu

  • The review page is the same; the status bar shows the wallet ERA picked (here Wallet_4, the test wallet). See SCAN QR: one button for everything.

    Review page 1 reached from SCAN QR; status bar reads Wallet_4
    Review page 1 reached from SCAN QR; status bar reads Wallet_4

  1. Point the ERA camera at the QR code on your phone. The review opens once the whole code is read.

    Scan QR page with the camera frame
    Scan QR page with the camera frame

Part 2: Check and approve

  1. On the first ERA LENS page, check Amount, From, To and Fee.

    Review page 1: Transfer, 0.0006 BTC, from, to, fee 0.000005 BTC
    Review page 1: Transfer, 0.0006 BTC, from, to, fee 0.000005 BTC

Note: "Change 1 … (verified)" means ERA has checked that the change address really belongs to your wallet. If that check fails, ERA refuses to sign — see Warnings explained.

  1. Swipe up. Check Change back — the part of your coins that returns to you.

    Review page 2: change back 0.000395 BTC, change address verified, totals
    Review page 2: change back 0.000395 BTC, change address verified, totals
To see every coin that goes in and out

  • Tap Inputs or Outputs.

    Nested Inputs and Outputs rows with address, path and amount
    Nested Inputs and Outputs rows with address, path and amount

  • Tap FOLD UP (or the back chevron) to return to the review.

  1. Swipe up to the last page. Check Sign Status and Network, then tap APPROVE.

    Review page 3: Outputs row, Sign Status Unsigned, Network Bitcoin, APPROVE
    Review page 3: Outputs row, Sign Status Unsigned, Network Bitcoin, APPROVE

Part 3: Return the signature

  1. Show the SCAN TO APPROVE QR code to your software wallet. It is animated; hold the phone still until the app has read it all.

    Animated signed-PSBT QR code on the SCAN TO APPROVE page
    Animated signed-PSBT QR code on the SCAN TO APPROVE page

  2. In the software wallet, finish the send (usually Broadcast or Send).

    Image coming soon — phone app after scanning ERA, showing the "broadcast" / "send" confirmation

  3. On ERA, tap DONE.

To cancel instead

  • On any review page, tap the back chevron. ERA returns to the SCAN QR page without signing.

  • On the SCAN QR page, tap the back chevron again to return to the wallet page.

  • On the SCAN TO APPROVE page, the back chevron returns to the review; nothing is sent until your software wallet scans the QR code and broadcasts.

Done

The SCAN TO APPROVE page closes when you tap DONE and ERA returns to the wallet page (to the Home screen after a Quick Sign). Your software wallet shows the transaction as sent (broadcast).

Trouble?

  • The APPROVE button looks greyed out → swipe up to the last review page; it becomes active there.

  • CHANGE FRAUD appears and there is only CLOSE → the PSBT claims a change address that is not yours. ERA did not sign. Rebuild the transaction in the software wallet and, if it happens again, stop using that software wallet.

  • "Fee is N% of the total value" appears on the review → the fee is unusually high (5 % or more of what you send). Check the fee setting in the software wallet before approving.

  • "UNKNOWN DESCRIPTOR" appears → this is a multisig transaction for a wallet setup that is not saved on ERA. See Warnings explained.