UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Audio (record players, hi-fi etc)

Notices

Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment.

Closed Thread
 
Thread Tools
Old 13th Aug 2019, 10:35 pm   #1
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Default Hacker Cavalier GP15 Circuit Diagram

Evening all, Just started on this player, it has a garrard AT6 mk2 deck. My question is, doe it use the same circuit as the Gondolier GP42? I can only find that one on Paul's DVD. (mine is the ECL86 variant) It's working to a degree but the output is VERY distorted and if the wick is turned up it will oscillate. I'm going through the amplifier as it has some of those horrible black plastic bodied electrolytics that are bound to need replacing.

Cheers
Rob
AD360 Rob is offline  
Old 13th Aug 2019, 10:39 pm   #2
Herald1360
Dekatron
 
Herald1360's Avatar
 
Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,528
Default Re: Hacker Cavalier GP15 Circuit Diagram

You'll likely find the GP15 info in one of the Yahoo Hacker groups' files. You'll need to register, but it's free.
__________________
....__________
....|____||__|__\_____
.=.| _---\__|__|_---_|.
.........O..Chris....O
Herald1360 is offline  
Old 13th Aug 2019, 11:11 pm   #3
electrogram
Heptode
 
Join Date: Jul 2008
Location: Hereford, UK.
Posts: 719
Default Re: Hacker Cavalier GP15 Circuit Diagram

I think there are minor differences, on the 15 the pentode anodes are fed directly from rect. cathode - via output transformer, and the cap associated with the bass control in the feedback loop has a different value, otherwise pretty much the same. Distortion may be due to grid coupling caps to the pentode sections being leaky. On the 42 these are always the reliable Mullard mustards but on most of the 15s I've seen they are Supamoulds and must be replaced

Last edited by electrogram; 13th Aug 2019 at 11:16 pm.
electrogram is offline  
Old 13th Aug 2019, 11:27 pm   #4
Nuvistor
Dekatron
 
Nuvistor's Avatar
 
Join Date: Aug 2013
Location: Wigan, Greater Manchester, UK.
Posts: 9,427
Default Re: Hacker Cavalier GP15 Circuit Diagram

Quote:
Originally Posted by Herald1360 View Post
You'll likely find the GP15 info in one of the Yahoo Hacker groups' files. You'll need to register, but it's free.
I have just checked, the manual is in the Yahoo Hacker Audio Group courtesy of Mark, a UKVRRR forum member.
__________________
Frank
Nuvistor is offline  
Old 14th Aug 2019, 9:18 am   #5
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Default Re: Hacker Cavalier GP15 Circuit Diagram

I'll join up then, thanks chaps. I'll let you all know how it goes with this player (or should that be Reproducer?)
AD360 Rob is offline  
Old 15th Aug 2019, 7:37 am   #6
crackle
Rest in Peace
 
Join Date: Mar 2011
Location: Basildon, Essex, UK.
Posts: 4,100
Default Re: Hacker Cavalier GP15 Circuit Diagram

Or you can download it from the Radio Museum. https://www.radiomuseum.org/r/hacker_cavalier_gp15.html

Mike
crackle is offline  
Old 16th Aug 2019, 2:55 pm   #7
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Default Re: Hacker Cavalier GP15 Circuit Diagram

Afternoon everyone, got a circuit diagram, there's very little difference between the gp15 and gp42. Anyway I replaced most of the electrolytics (way off value and leaky) also the 2 grid coupling caps, checked all the resistors and they were all within tolerance so left them alone. Amp now is working properly, no hum, no distortion and voltages appear correct. It's running a lot cooler too so happy about that. Now to move on to the deck.. It's been abused (transit screws tightened so much they've pulled through the metal and spring cups detached) also the arm rest is broken. Does anyone have one? It's a garrard AT6 mk2? I'll also post this in the parts wanted section of the forum.

Rob
AD360 Rob is offline  
Old 16th Aug 2019, 4:42 pm   #8
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Default Re: Hacker Cavalier GP15 Circuit Diagram

My mistake, it's not the spring mounts that have been pulled out, just the thread inserts for the transit screws (which is bad enough)
AD360 Rob is offline  
Old 18th Aug 2019, 11:10 pm   #9
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Smile Re: Hacker Cavalier GP15 Circuit Diagram

Quote:
Originally Posted by AD360 Rob View Post
Now to move on to the deck.. It's been abused (transit screws tightened so much they've pulled through the metal and spring cups detached) also the arm rest is broken. Does anyone have one? It's a garrard AT6 mk2? I'll also post this in the parts wanted section of the forum.

Rob
After some exhaustive research (thanks google) I have found the arm rest is the same as the DECCADEC variant of the AT6 Mk2 and SP25. in case you're wondering, these decks were made by Garrard and had a modified arm so you could plug a Decca Deram cartridge straight into the arm. . . no headshell required ! Anyway I managed to find an arm rest on eBay so happy now
AD360 Rob is offline  
Old 23rd Aug 2019, 6:26 pm   #10
AD360 Rob
Hexode
 
AD360 Rob's Avatar
 
Join Date: Jun 2012
Location: Chester, Cheshire, UK.
Posts: 421
Default Re: Hacker Cavalier GP15 Circuit Diagram

Afternoon all, getting to the end of this record reproducer now, it's all working nicely apart from the pilot light behind the controls. The bulb has failed. The original type is an 8.5v 0.3a mes. Try as I might I can't find anything like that spec online. Plenty of lower voltage at the right current but the only higher voltage ones are 12v but 0.2a.is there a known alternative for the original?

Thanks
AD360 Rob is offline  
Old 23rd Aug 2019, 9:22 pm   #11
music-centre
Heptode
 
Join Date: Sep 2007
Location: Brentwood, Essex, UK.
Posts: 687
Default Re: Hacker Cavalier GP15 Circuit Diagram

Seems a strange voltage to use - is it definitely not a 6.5v 0.3a ?
Steve.
music-centre is offline  
Old 23rd Aug 2019, 9:43 pm   #12
Nuvistor
Dekatron
 
Nuvistor's Avatar
 
Join Date: Aug 2013
Location: Wigan, Greater Manchester, UK.
Posts: 9,427
Default Re: Hacker Cavalier GP15 Circuit Diagram

Manual states 6.5v 0.3A
Attached Thumbnails
Click image for larger version

Name:	A2DF0A61-DCDF-4948-8B1F-4C997F84AC40.jpg
Views:	73
Size:	26.9 KB
ID:	188802  
__________________
Frank
Nuvistor is offline  
Old 23rd Aug 2019, 10:26 pm   #13
Herald1360
Dekatron
 
Herald1360's Avatar
 
Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,528
Default Re: Hacker Cavalier GP15 Circuit Diagram

Might just be a poor stamped marking on the old bulb. 6 and 8 are pretty similar in some fonts apart from closure of the top bit.


Or someone just wanted the bulb to last for ever (and was unlucky anyway).
__________________
....__________
....|____||__|__\_____
.=.| _---\__|__|_---_|.
.........O..Chris....O
Herald1360 is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 5:49 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.