8080DB chassis question

[DougBrewster]

when Sansui did several upgrades on the 9090DB in late '77 they included a "gold" coloured chassis (Cad plated?). Did the 8080DB get the same chassis upgrade? Anybody got one?

 

[Robisme]

I believe so.. Search Google images. I see both.

Though, I'm not sure which came first. I think the goldish one did.

Rob

 

[naderpe]

Yes. Later on both the 8080db/890db had the gold colored finish applied. Quite sure it is not cadmium plate. From my experience the gold finish looks better than the earlier chassis but was no better at withstanding corrosion. There earlier gray type also had a finish to the metal.

 

[LBPete]

The chassis plating changed to yellow zinc late in production sometime after they changed the driver boards to use the diode based bias control.

- Pete

 

[DougBrewster]

OK, thanks for your input guys

 

[nosirrah]

The gold color on the aluminum chassis is due to the type of Alodine used as a corrosion inhibitor. Alodine 1000 results in the grey appearance, the gold is Alodine 1200. The only benefit of the 1200 in this application is that the gold color makes the coating inspectable after application, assuring all surfaces were treated.

 

[LBPete]

Does Alodine work on steel? I thought it was an aluminum treatment.

- Pete

 

[LBPete]

It all depends on how the two units were stored over the years. The later production one may have been in a damp basement for years.

- Pete

 

[nosirrah]

No, Alodine is an aluminum finish only. If it's a steel part then the differance is in the cadmium plating. The gold color is from a post plating chromate dip whos only purpose is to make the finish inspectable. Regular cad plate will give a dull grey/silverish appearance.
As far as deterioration is concerned LBPete is correct. Moisture is the issue with all types of corrosion, especially if there's any salts in the air, like near the ocean.
Use a magnet to verify your substrate material and if it's aluminum you can easily touch up alodine, cadmium on steel not so much.

 

[DougBrewster]

well it's certainly not aluminium because it's magnetic...

 

[skippy124]

IMO It will most likely be zinc plate with yellow passivation (zinc plating can be left natural, or have a clear or yellow passivation process after the zinc plating has been done)

Cheers

John

 

[LBPete]

It's most likely yellow zinc.

- Pete