09-09-2012, 02:01 PM
Alan, the one on the left appears to have "wel" printed on it, maybe welwyn?
Lawrence.
Lawrence.
ERG resistors
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09-09-2012, 02:01 PM
Alan, the one on the left appears to have "wel" printed on it, maybe welwyn?
Lawrence.
09-09-2012, 03:44 PM
Alan
I have noticed that some of the larger or higher wattage resistors have very short leads with additional lengths of lead soldered on to them. This must have been undertaken by the manufacturer as most of these are still in there sealed bags. This may suggest that other types of terminal end could have been soldered on as required. Rob
if all else fails...read the instructions!
09-09-2012, 05:06 PM
I recently bought one like that from Bardwell's. What surprised me was that the data on the side looked to have been hand-written.
- Joe
09-09-2012, 05:21 PM
I've seen quite a few of those over the years - neat cursive writing in sort of white paint. Don't know what they used to apply it. I think the green coating is vitreous. Looks like they'll come in handy for power sections of radios, if the rather odd values are within say 10% of that required. (Is that why you bought them Rob?). No doubt they were expensive to produce!
Regards, David.
BVWS Member. G-QRP Club Member 1339. 'I'm in my own little world, but I'm happy, and they know me here'
09-09-2012, 05:56 PM
I paid less than £10 (inc P&P) for a box full which must contain a couple of hundred assorted values. Whilst working on the VHF90's (2 of them with a third as a reference), I realised I didn't have much in the way of power resistors. I'm not sure how many of these will have useful values in these radios thought!
Rob
if all else fails...read the instructions!
09-09-2012, 07:20 PM
You might find that if you don't have one within 10% tolerance either way of what you need, that two in parallel would fit the bill, and of course share the load. No need to do the sums Rob: http://www.1728.org/resistrs.htm Most, though not all, radios seem to have a bit of space around the power section if you need to double them up.
I dare say the power handling and reliability of those resistors will be superior to modern ones (the square section white jobbies). You won't need to use many to recoup your tenner!
Regards, David.
BVWS Member. G-QRP Club Member 1339. 'I'm in my own little world, but I'm happy, and they know me here'
10-09-2012, 09:29 PM
Lawrence,
You may well be right. If you search 'vintage wirewound resistors' (no quotes) in eBay you get hits both for Welwyn - wrong spelling, but its eBay - and ERG. I certainly remember WW Resistors with that construction, but can't actually remember either the date or Manufacturer. Alan
11-09-2012, 01:29 PM
(09-09-2012, 03:44 PM)Bushbaby Wrote: Alan Hi Rob, I've come across wire-wound resistors with the added extensions and they were done using high temp solder - my iron had no effect at all. I assume it was done like this to allow the resistor to get extremely hot without the risk of melting the solder joint and the extension meant a regular solder joint could be used as the extension was further away from the heat source. Of course that's just a guess on my part Cheers, John
Time flies like an arrow, fruitflies like a banana!
11-09-2012, 06:06 PM
I have some 3W 5% resistors of the same type in Alans 'scope, definitely Welwyn.
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