Search found 22 matches

by JeffreyC
Sat Sep 21, 2013 5:34 pm
Forum: Hylight era Amps
Topic: 74 DR504 replacement indicator lamp jewel...
Replies: 1
Views: 600

74 DR504 replacement indicator lamp jewel...

Hey guys - where can I get a replacement indicator lamp jewel for my vintage Hiwatt?
The bulb still works fine, but the red jewel came apart.

Thanks!
by JeffreyC
Fri Sep 21, 2012 1:28 pm
Forum: Hylight era Amps
Topic: 74 DR504 back cover....
Replies: 1
Views: 908

74 DR504 back cover....

So, the back cover has always been missing on my old Hiwatt. Anywhere to get a replacement that will fit?
I usually don't take it out gigging, but I might if I had a back cover.

Thanks.
by JeffreyC
Wed Dec 01, 2010 2:44 pm
Forum: Hylight era Amps
Topic: Advice on 74 Hiwatt DR504......
Replies: 2
Views: 1038

Re: Advice on 74 Hiwatt DR504......

Thx a million Mark....appreciate your thoughts. Yeah, I realize they are clean machines and maybe "sing" was the best word to use - I do use these amps as a clean slate for great pedals ala Gilmour, but the base tone is important obviously. The Reeves is a clean machine too, but at low vol...
by JeffreyC
Tue Nov 30, 2010 9:48 pm
Forum: Hylight era Amps
Topic: Advice on 74 Hiwatt DR504......
Replies: 2
Views: 1038

Advice on 74 Hiwatt DR504......

Hey guys - posted this thread a little while ago on TGP - http://www.thegearpage.net/board/showthread.php?t=791859 I'm thinking I may want to try my hand at replacing the coupling caps in my amp, but want some Hiwatt expert thoughts first. Before reading the thread - here's a little history on my am...
by JeffreyC
Wed Oct 20, 2010 4:42 pm
Forum: Hylight era Amps
Topic: Early vs Mid 70's DR504 preamps....
Replies: 1
Views: 856

Early vs Mid 70's DR504 preamps....

Ok, so I've been looking over the schematics on Mark's site and I can see some component value differences here and there, but I'm wondering what are the main differences in these two preamps and how do they effect tone? Also, when did they change to the mid 70's version and what's the simplest way ...
by JeffreyC
Thu Mar 25, 2010 1:28 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Thanks Mark. Yeah, what you're saying makes total sense to me. I believe these were probably matched by AES, but don't know for sure.
by JeffreyC
Wed Mar 24, 2010 2:39 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Might this spike activity in a whole new market for "NOS" Modern Production tubes ? Dave P.S. On a related note, I see that AES is now offering "broken-in / tested" JJ E34L's. I imagine that's in response to an unacceptable DOA rate. Gosh, I hope so!! Would be nice since the NOS...
by JeffreyC
Wed Mar 24, 2010 1:40 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

This is for DR504 - no inner/outer pairs. ;) I bought matched pairs from Antique Electronic Supply. One pair biased in around 35ma and is running fine. I got the other pair down to around 46 ma at the lowest possible bias setting on the trim pot and so they were still red plating. The pair that I wa...
by JeffreyC
Wed Mar 24, 2010 12:25 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Hey guys, thought I'd provide an update on this....could not wait for the VHR mod as I need this amp to be my backup for gigging. I took my amp to Bruce at Mission Amps to do the bias mod. He did a nice non-invasive job. :) I tried the two pairs of Winged C's last night. I was able to bias one pair ...
by JeffreyC
Sat Mar 06, 2010 5:08 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Pair 2 seems sufficiently matched. Pair 1, not so much. And, the two Pairs aren't in the same range. Did you order a matched quad or two matched pairs (there's a difference)? AES is a reputable firm. It would surprise me if they shipped a matched quad like that. Have you contacted them with your fi...
by JeffreyC
Sat Mar 06, 2010 3:30 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Anyone care to comment on the Winged C measurements? I thought maybe it would surprise some of you....maybe I should have purchased from somewhere else? Also - question about my master Volume pot....I've noticed that I don't get much increase in volume until quite a bit past the halfway mark...proba...
by JeffreyC
Wed Mar 03, 2010 11:29 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Hehehe, this is fun - 2 brand new matched pairs of Winged C's from Antique Electronic Suppy - Pair 1 Milliamps - 77.6, 84.4 Plate voltage - 468, 468 Pair 2 Milliamps - 66.9, 67.3 Plate voltage - 478, 477 Bummer, I was looking forward to these being close to where they should be. Anyone care to help ...
by JeffreyC
Wed Mar 03, 2010 7:53 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Cool, thanks Mark. Will these be on the new items section of the VHR site?
by JeffreyC
Tue Mar 02, 2010 4:52 pm
Forum: Hylight era Amps
Topic: Bias and plate voltage measurements.....
Replies: 26
Views: 5131

Re: Bias and plate voltage measurements.....

Any word on the bias kits yet? I've got 2 pair of Winged C's on the way, but I think ultimately I'd
like the flexibility of being able to experiment with different tubes.