Unfortunately, I recently received a well-used Beolover Beogram shipping container from Australia. Inside was a Beogram 4002 (5501) that I had previously restored in 2016. The 5501 model is unique because it represents a short-lived transitional version produced during B&O’s shift from the Beogram 4000 to the 4002. Although the 5501 features the analog control system of the 4002 series (unlike the 4000’s more sophisticated hard-wired digital logic system, which was sadly simplified in the 4002), it retains the mechanical carriage position switches found in the 4000. It also boasts an intriguing rotary encoder for detecting the end groove. You see, the Beolover has a certain fondness for the 5501, but encountering it for a third time brought a tinge of sadness.

The reason for its return to my workbench was a malfunction. The problem was evident upon plugging it in: the solenoid immediately activated, and the deck became unresponsive to any keypad input except for 33/45 RPM adjustments.

To investigate, I removed the hood and aluminum panels:

A little exploration revealed a short circuit in the TIP41 transistor responsible for driving the solenoid:

Replacing it with a new one restored normal solenoid operation and responsiveness to the arm lowering key. This image displays the newly installed component:

I also replaced the discolored 8.2 Ohm solenoid resistor (4R1),

with a modern 2W rated one:

These images illustrate the voltage measurements across the activated solenoid

and the resistor:

These readings indicate the resistor operates at approximately 1.2W. The original resistors have a 1W rating, slightly insufficient for this application.

Despite these fixes, the deck remained unresponsive to the four keys controlling carriage movement. After examining some transistors in the electronic switch, I realized the carriage motor itself had failed. I removed and opened it, discovering a corroded wire disconnected from its motor tab. The other wire also detached easily with slight movement:

I cleaned the terminals, soldered 22AWG wires to them, and replaced the deteriorated soundproofing with a custom-cut piece of self-adhesive neoprene rubber:

After reinstalling the motor,

all functions were restored. As a preventative measure, given my experience with AC motor type Beograms since 2016, I decided to address the AC motor driver transistors located beneath the main PCB, which are prone to issues. This image shows the original transistors, 0TR2 and 0TR3:

I also discovered a missing hood attachment bolt spring near the transistors, explaining its absence during disassembly. Here’s one of the original transistors, the PNP TIP32 (0TR3, on the right):

I replaced it with a modern BD438, noting the reversed emitter and base leads on these types:

The NPN TIP31 was also replaced with a complementary BD437 (also with reversed wiring). Both new transistors are shown installed here:

I will conduct further testing on this Beogram. If no other issues arise, it will journey back across the ocean to Australia!