Paul Howson’s Website: Projector Bench

Refreshing a Garrard 401 Turntable

Mon, 08 Sep 2025 00:00:00 +0000

As a teenager in Melbourne circa 1970, I designed and put together a high quality hifi system, including construction of a substantial wooden cabinet to house all the components.

This accommodated a Quad 33/303 preamp/power amp combination, a Revox A77 tape recorder, a Garrard 401 turntable and SME 3009 tone arm, together with a set of three Ortofon phono cartridges — one for 78s, one for mono microgroove, and an Ortofon SL15 for stereo discs. Speakers were Celestion Dittons supplemented with a set of Stax electrostatic headphones for personal listening.

Adjusting the Tracking Weight for a VM670SP Mono Cartridge

Mon, 28 Jul 2025 00:00:00 +0000

The Audio Technica VM670SP is a mono moving magnet cartridge. The stylus has a 3.0 mil (thousandth of an inch) curvature radius suited for playing 78s.

I recently purchased one of these from Vinyl Revival in Melbourne to replace an Ortofon Type C cartridge originally purchased circa 1970 (see text box “The Ortofons Reach their Use-By Date”).

The VM670SP manual specifies a tracking force of 4.5 to 5.5g (5.0g standard).

Replacing the Battery in an iPhone SE

Thu, 05 Jun 2025 00:00:00 +0000

My iPhone SE, purchased in 2017, had started to bulge. And the battery would not sustain a charge for more than a few minutes before the phone would die. I had taken to running it off the charger when needing the phone for a bank login or a 2FA authenticator code. But running a device with a severely worn out and bulging battery is not advised, and even dangerous.

The iPhone with the screen detaching from the body due to internal pressure from an expanding battery. Time to replace the battery!

There were three versions of the SE and this was the first one. Apple in Australia no longer offered a battery replacement service, classifying this device as a “vintage” product.

Piece by Piece Re-assembly of Cleaned Parts — General Advice and Approaches

Thu, 05 Dec 2024 00:00:00 +0000

Some of the disassembled EIKI NT parts waiting to be put back together.

Referencing the EIKI Service Manual

Having a scan of the Service Manual for the EIKI Model N Series proved an essential aid in the process of disassembly and re-assembly.

For example, when it came to cleaning the lens holder and gate assembly, the exploded construction diagram of this somewhat complex and delicate mechanism was an essential pre-requisite. I was able to partially disassemble the gate, clean the parts and re-assemble it.

Beginning the Disassembly Process

Tue, 23 Mar 2021 00:00:00 +0000

As described in the last post, I had removed the amplifier and power transformer, then removed and cleaned the sound drum pressure roller on the EIKI NT projector.

A close inspection of the mechanisms in the rear of the projector revealed traces of rust on some parts and a general build up of dust and grime. Clearly this machine needed a more thorough overhaul, so that was the process which I now began. Fortunately I was able to locate a scanned version of the Service Manual for the Model N Series, dated May 1980, which proved a valuable guide during the disassembly process.

More Signs of Moving Parts that Had Seized Up

Mon, 20 Jan 2020 00:00:00 +0000

Having attended to the malfunctioning speaker and the broken supply and take-up arm belts, more little problems started to make themselves apparent on the EIKI NT projector.

The Auto-Loading Guide That Was Not Retracting Properly

This projector has an auto-loading feature. When engaged, the mechanism arranges itself so that the film will self-feed from the supply sprocket, via the gate, sound drum and various rollers to emerge at the rear of the machine, ready for manual threading onto the take-up spool. The auto-load guide is positioned immediately after the supply sprocket and guides the film to form a correctly-sized loop and thence into the film gate guides.

Broken Supply and Take-Up Belts on the EIKI NT

Mon, 02 Sep 2019 00:00:00 +0000

The ailments with the EIKI NT did not end with the speaker repair.

While working on the projector, I discovered that the supply arm spool (the one at the front of the projector) was not taking up the film as it should when the projector is put into reverse.

Removing the cover from the supply arm revealed that the rubber belt which drives the supply spindle was broken in two places. It might have been that way for a while because I was not in the habit of using the projector in reverse or using it to rewind film. (See section below “The Mechanics of the EIKI NT Supply Arm”.)

A Failed Speaker on the EIKI NT

Wed, 10 Jul 2019 00:00:00 +0000

The EIKI NT which I had purchased on eBay had ceased to play any sound through the forward-pointing speaker that’s mounted in the rear cover. For quick previews of sound films, this internal speaker usually suffices.

The rear cover of the EIKI NT showing the front-facing internal speaker.

Some detective work was required to track down why this speaker was not working.

I noted that the exciter lamp was still glowing, so I connected the two external speakers in the removable front cover to the speaker output socket on the front of the projector. Flicking a piece of paper past the sound drum produced thumping in these external speakers. Hence the photocell and the amplifier were working. It had to be a problem with the internal speaker.

A Second Hand 16mm EIKI NT1 Needing Some TLC

Mon, 17 Jun 2019 00:00:00 +0000

In 2010 I was on the lookout for a semi-manual-loading EIKI 16mm film projector in good condition and came across an EIKI NT1 on eBay which looked very promising. The vendor claimed that the machine had been purchased new and used only a few dozen times after which it had “sat in a wardrobe” for many years. Exactly when it had been purchased was not clear, but the serial number (69064) indicated a later model EIKI NT. So I snapped up this apparent bargain.

About this Blog

Thu, 01 Jan 2009 00:00:00 +0000

Growing up in a family involved in film, radio, television and theatre, I have always been interested in the technologies associated with these, in particular an interest in electronics which eventuated in studying electrical engineering at Monash University.

This blog started with a project undertaken in 2009 to rebuild an old Pathé Marignon 9.5mm film projector which had belonged to my father, Denzil Howson.

Posts about restoration of the Pathé Marignon projector are currently on blogspot at the following url: