Beta10Pin is the hardware adapter that allows connection of Beta camera with 14-pin (K-type) cable to EIAJ 10-pin (J-type) video tape recorder (VTR). Like Sony CMA-1010 but more functional.

The main target VTR is Panasonic/National NV-180 which has a small footprint, full direct drive VHS 4-head die-cast transport and non-EIAJ-standard serial link to a camera. But this adapter should work with other VTRs that have EIAJ 10-pin connector for a camera. Also, older Panasonic/National NV-100 VTR and its derivatives have a serial link to the camera but its protocol is unknown and compatibility not tested.

Why not just use CMA-1010?

It's quite hard to find, it's pretty big, it has thick and stiff cable and does not support all features of Sony Beta cameras and features of serial link control for Panasonic NV-180.

Most of all CMA-1010 can not monitor if record process on a VTR has started and just lights up tally light in sync with button press on the camera, which causes false recording indication and loss of footage. Also low battery indication function is not available. And Rec Review function is unavailable.

• Provides power from a VTR to a Beta Camera
• Allows video and audio to be transfered from a camera to a VTR when VTR is in record mode
• Allows video from a VTR to be displayed in a camera's viewfinder when VTR is in playback mode
• Works both with PAL and NTSC VTRs and cameras
• Converts level and pulse pause commands from a camera to level "unpause" signal for a VTR (camera record button mode is auto-detected)
• Allows "Record review" mode (via "RR" button) through picture search
• Monitors VTR's state via serial link and indicates control errors via tally light blinking
• Monitors supply voltage and indicates low battery by blinking tally light in a camera
• Monitors camera's power consumption and puts VTR in pause and stand by to preserve energy when camera is turned off
• Allows powering camera without VTR from USB-C PD/QC source (12V input)
• Outputs video and audio through 2xRCA if not connected to a VTR through 10-pin EIAJ connector

Adapter utilizes Atmel AVR MCU for logic, serial link and voltage measurement. Firmware project is done in AtmelStudio 7.

Target MCU is ATmega 88 (either variant). But firmware should be compilable and working on ATmega 168/328 variants as well. ATmega 48 is not supported due to low ROM capacity.

MCU can be clocked from internal 8 MHz RC-oscillator but external 8 MHz Xtal is recommended for precise timing.

Due to dependance on ADC measurements and proper serial connection with VTR MCU should run on voltages from 4.5 V to 5.0 V. Thus BOD (Brown-out Detector) is enabled by MCU fuses.

Adapter fits onto single PCB (BETA10P.M.xx) of size ~97x30 mm. PCB project is done in Sprint Layout 6.

14-pin Beta camera connector, 2xRCA connector and USB-C PD/QC trigger are soldered onto the PCB. 10-pin EIAJ VTR connector connects via its cable with individual wires connected to the PCB through connectors.

The main PCB can be wrapped with shrink tube or slid into plastic/metal case. As an alternative project contains files for 4 more PCBs to assemble case from:

• BETA10P.F.xx (29x35 mm) for the front part (holds 14-pin camera connector)
• BETA10P.B.xx (29x35 mm) for the back part (2xRCA, USB-C, cable to 10-pin EIAJ connector)
• BETA10P.S.xx (98x35 mm) for the both sides (2 pcs per adapter)
• BETA10P.C.xx (98x28 mm) for the top and bottom parts (2 pcs per adapter)

"xx" at the end denotes revision of each PCB. Release can contain boards of different revisions ("xx" doesn't have to be the same).

Provided "case boards" also contain copper fill to shield the insides and connect with main PCB's common.

When assembling, cable should be routed through the back PCB before connecting to the main PCB. 14-pin Beta connector should be put through the front PCB before soldering to the main PCB.

Back PCB should be screwed to the RCA connector block. Front PCB should be screwed to the 14-pin Beta connector through soldered nuts.

Case cover is assembled by soldering top and side parts together at the 90 degree angles. After that assembled cover should be slid onto the main PCB from the top and soldered in all corners to the front and back PCBs.

Bottom PCB has to be put last and soldered on its perimeter to the case.

Cameras can have different "trigger modes" for the record button that usually can be selected with a switch at the bottom of the camera.

Usual record button modes:

• default at "low", toggling state with each button press
• default at "high", toggling state with each button press
• default at "high", producing ~200 ms negative pulse with each button press

CMA-1010 adapter only supports two modes and for selecting between those you have to open up its case and move a physical switch inside. Beta10Pin auto-detects trigger mode of the camera and responds on every record button press on the camera correctly.

After connecting adapter to supported VTR (NV-180 or other from "Supported VTRs" list), to Beta camera and powering on the VTR adapter establishes serial link with the VTR and is held in "idle" mode.

flowchart LR;
    idIdle(Idle)-- first press of record button -->idPause(Paused recording);
    idPause-- record button -->idRec(Recording);
    idRec-- record button -->idPause;
    idPwrsv-- record button -->idRec;
    idPause-- 2 minutes of pause -->idPwrsv(Power save pause);
    idPause & idRec-- camera turned off -->idPwrsv;
    idPause & idPwrsv-- RR button pressed -->idRR(Record review);
    idRR-- RR button released -->idPause;
    idPause & idRec & idPwrsv & idRR-- error event -->idErr(Error);
    idErr-- record button -->idIdle;

When "Camera" switch on the front of the VTR is set to "Normal" VTR is controlled by its front panel and camera adapter is ignored. User should eject the loading tray, put a recordable VHS cassette inside and close the tray.

Next, "Camera" switch on the VTR should be moved into "Remote" position to allow the adapter to take control.

First press of the record button on the camera arms the adapter, that commands to set "record + pause" mode to the VTR. At the same time tally light on the camera blinks fast and VTR spins up its head drum and loads the tape inside. When VTR gets ready tally light goes out and adapter settles in "paused recording" mode, recording does not start yet.

"Paused recording" is the main mode of the adapter, ready to begin recording process. User can frame a shot using viewfinder of the camera and arm camera's "Fader" function if necessary. When record button is pressed in this state the adapter goes into "recording" mode and commands the VTR to clear pause and start recording process. Tally light should light up and stay solid.

If record button is pressed while adapter is in "recording" mode, adapter returns back to "paused recording" mode, sets "record + pause" for the VTR and turns off tally light.

If camera is switched into "power save" mode or gets disconnected, the adapter goes into "power save pause" mode. The same happens if "paused recording" mode was held for more than 2 minutes. In this mode VTR keeps tape loaded in but stops the drum and deactivates most of the circuits, dropping power consumption five-fold.

When in "paused recording" or "power save pause" modes "RR" button can be pressed and held on the camera (if it's present). That puts adapter into "record review" mode when the VTR switches to playback in reverse and displays what was just recorded in camera's viewfinder. If record button is pressed while "RR" button is held, playback direction is reversed. As soon as "RR" button gets released adapter goes into short "pause" and then returns into "paused recording" mode putting the VTR once again into "record + pause" from current place on the tape. While VTR switches from recording to playback and vice versa the tally light on the camera blinks fast.

If any abnormal situation occurs, the adapter senses that and falls into "error" mode which is indicated by slow blinking of the tally light on the camera. VTR should unload the tape and stop. "Error" mode can be cleared by single press of the record button on the camera.

Examples of the sources of the error:

• Trying to start recording without a tape in the VTR (error code 1)
• Trying to record on a write-protected tape (error code 2)
• VTR or tape malfunction (error code 3)
• "Camera" switch was moved from "Remote" position and adapter lost control over the VTR (error code 4)

If battery level gets too low, adapter makes a short blink of the tally light once a second.

If the VTR does not have a serial link (or the link has failed for any reason) adapter senses that and falls back into "direct" control mode. In this mode adapter operates more or less like CMA-1010.

The only control mechanism in this mode is "pause" wire in the 10-pin connector (pin 6) with no feedback from a VTR to a camera. No monitoring of the VTR state and no direct control of VTR mode is available in this mode.

With every press of record button on the camera adapter will toggle "pause" signal to the VTR and tally light on the camera. If VTR was in "paused recording" mode it will go into "recording" mode, if VTR was in "recording" mode it will go into "paused recording" mode. If there was no tape in the VTR or recording mode was not armed probably nothing will happen on the VTR side (while tally light could still light up) leading to loss of video material.

If adapter senses that VTR switched into playback mode, firmware will toggle "recording" mode to "paused recording" and turn off tally light.

"RR" button on the camera will have no effect on the VTR, no "record review" functionality is available in this mode.

If camera is switched into "power save" mode or gets disconnected, the adapter goes into "paused recording" mode and turns off tally light on the camera.

If battery level gets too low, adapter makes a short blink of the tally light once a second.

• Working basic control (VTR controls video path relay, camera controls pause line to VTR)
• Working voltage monitoring and indication in camera
• Working camera connection detection and NV-180 standby function operation
• Working serial link detection and RX/TX
• Working state machine while communicating with NV-180 VTRs through serial link
• Working "record review" processing

• Test adapter with other VTRs (without serial link and standby control)

Program copyright 2024.

This program is free software. Licensed under the Apache License, Version 2.0 (the "License");