Old 810 Transmitter: What's it worth? Restorable?

[WA1JFX]

I hear the sentiments/philosophy about preserving the old timers work from the old days when AM was on the maturity curve just prior to SSB.  In looking at old buzzard gear on eBay and elsewhere, there are are many variations.  Old Wrinkle must have been a phase/fad...  Wow, I didn't realize the history and technology is so revered my many still today.  Thank you!

I took a couple more photos.  Note the white spots on the wrinkle finish in one photo.  Can this be removed without harming the originalality?

What is that iron candle-looking "thing" next to the 810 final?

Russ

[KA8WTK]

What is that iron candle-looking "thing" next to the 810 final?

I think you are referring to the neutralizing cap. These were used to reduce the possibility of parasitic oscillations. You want the final amplifying the frequency you want, not oscillating by itself on other frequencies.


Bill KA8WTK

[KM1H]

Its not something that interests me as I already have enough old iron but I hope somone on here goes for it.

Id be interested in learning more about the receiver and might want to take a go at that.

Carl

[W7TFO]

I see WW2 military transmitter parts in it, so it is a post-war build.

73DG

[KM1H]

I think you are referring to the neutralizing cap. These were used to reduce the possibility of parasitic oscillations. You want the final amplifying the frequency you want, not oscillating by itself on other frequencies.

Those are two completely seperate things and treated differently.

Neutralization is to keep the amp from becoming a TPTG oscillator somewhere within the range of the tuning caps due to the tubes Cgp allowing a feedthru path. To compensate a sample of the plate RF is sent back out of phase to the grid effectively acting as a notch filter to cancel the feedthru.

A parasitic is a VHF oscillation caused by a combination of tube structure and its internal capacities and the circuit between the anode and the output network. It is normally suppressed (Its called a parasitic suppressor naturally) by a few turns of wire around a carbon resistor. Its purpose is to suppress the parasitic from even occuring and sbsorbs very little power if designed correctly.

Carl

[w3jn]

I took a couple more photos.  Note the white spots on the wrinkle finish in one photo.  Can this be removed without harming the originalality?


Russ

Restoring black wrinkle is really easy, unless it's flaking off.  Pull the meters and other stuff off the panel, get some Westley's whitewall cleaner, and wet the panel down with water in a sink.  Then spray the hell out of it with Westley's, scrub with a brush, and rinse well. 

If all the crap's not gone, then get some black satin spray paint.  Dampen a lint-free rag with mineral spirits, spray a bunch of paint into the rag, then apply to the front panel like you would be waxing it - circular motions, keep moving.  Add paint and thinner to the rag as necessary and even the paint out.  It'll look brandy=new when you're done.

[Opcom]

I'd like it but no room and no $$ since my truck just ate $1500 last week.