Dynatron Henley RG33W radiogram

[peter_sol]

That instruction book covers all those models. it does not mean that the Henley is a RG33W

[Vintage84]

I read it as the Henley being the RG33 and Richmond the RG34, etc.

I believe my model is the RG33W.

[Vintage84]

Here's a couple of photos of the radio section. The back of one of the valves looks like it could be a problem...

I'll try to find the service documents so that I can change any dangerous capacitors, etc. Which are the capacitors that are likely to cause problems?

[Edward Huggins]

You don't need to change capacitors for the sake of changing them! The key caps will be those associated with smoothing, cathode bias and inter-valve coupling - but if you have no previous experience, then don't start on this without getting some hands-on support from a Member of this Forum. It's a super unit and worthy of attention, but of the right kind. Edward

[Nickthedentist]

Originally Posted by Vintage84

I read it as the Henley being the RG33 and Richmond the RG34, etc.

So did I.

It looks like a really well-built machine, and the chassis is in virtually mint condition.

N.

['LIVEWIRE?']

I'd replace all those Red & Yellow Plessey Electrolytics for a start. To me they have become 'replace on sight' in anythiing!

[julie_m]

That's an impressive array of glassware I think I can spot an EZ81, ECC83 and four ECL82s. It should certainly have plenty of oomph when it's turned up!

The most important capacitors to replace are the DC blocking capacitors on the grids of the pentode sections of the output valves, because they can cause a nasty cascade failure if leaky.

[Nickthedentist]

Agree with both posts 25 and 26.

Note that the RG33S seems to be an entirely different beast, being all-transistor. Also, the RG22/3 is a lesser machine with a mere 5 valves, and as Graham implies, the "Cliveden" is the RG23 not RG33 as Paul describes it in the index.

OTOH, the RG21 is described as using 9 valves. Is your line-up: ECC85 ECH81 EBF89 ECC83 EM84 ECL82 ECL82 ECL82 ECL82?
http://www.service-data.com/section..../1/rg21-henley

[peter_sol]

It was silly of Dynatron to use the same numbers for completely different models.
Who knows what the prefixes of "W" and "S" stand for.
"S" maybe Solid State.

[Nickthedentist]

Yes!

It may be that the numbers are the cabinet style and the suffixes represent the chassis fitted, i.e. the opposite way round to normal practice.

[ronbryan]

Nick seems to have got it in one (post 27). The RG21 is a "Henley" according to the R&TVS sheet.

Ron

[Station X]

There must be more than one "Henley". This issue of Wireless World from 1964 shows a picture of a Dynatron Henley Model RG33W on page 441.

http://www.americanradiohistory.com/...ld-1964-09.pdf

[peter_sol]

Judging from the photo's, that is the one vintage 84 has, so he was correct.
All most confusing.

[Station X]

Given that this radiogram worked before the piano keys were lubricated and the fuse blew, perhaps the best course of action would be to replace the fuse and see whether it still works.

If it does then selective capacitor replacement would be in order. Perhaps the grid couplers and the Plessey electrolytics?

[Vintage84]

Originally Posted by Station X

There must be more than one "Henley". This issue of Wireless World from 1964 shows a picture of a Dynatron Henley Model RG33W on page 441.

That's the one (see attached).

I believe there are 9 valves, but will confirm the order tonight.

Unfortunately, replacing the fuse didn't do anything... Are there any obvious things I should check first?

[Nickthedentist]

Have you got a multimeter, and do you know how to use it?

[Station X]

Originally Posted by Vintage84

Unfortunately, replacing the fuse didn't do anything... Are there any obvious things I should check first?

One simple thing to check is whether the valves light up.

[Vintage84]

Originally Posted by Nickthedentist

Have you got a multimeter, and do you know how to use it?

Yes, I have one and know how it works - just haven't ever used it for testing this type of kit!

[Nickthedentist]

As a start, unplug the machine, set the meter to its lowest ohms range, connect the probes to the plug's L and N terminals, and see what the meter says both with the power switch on and off.

If the primary of the power transformer, its wiring, switches and fuses are OK, you should read a few tens of ohms with the switch on, and infinity (1- on a digital meter) with it set to off.

N.

[Vintage84]

Hi Nick,
Just checked this and it performs as you described.

Originally Posted by Station X

One simple thing to check is whether the valves light up.

The valves aren't lighting up.