jmd 1 head fuse keeps blowing

JMD1 Head and Combo

Moderator: longfxukxnhair


Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 30 May 2017, 16:57

Great idea... I just put a new fuse in, so if it blows ( without the EL's - which are new.... ) it will narrow it down somewhat.... Thanks..... I'll edit my test results after I try your method......

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 30 May 2017, 21:05

I removed all the power tubes... Turned the power on and waited a few min.. Turned the standby switch on and off several times.. The fuse stayed intact. Did not blow.. So I'm assuming the power tubes are the culprit.. Or one of them anyway... Now to determine which one and how to fix it.. Or Should I just take it in.. Or keep on troubleshooting.. Thoughts ??? ... And Thank you very much for your help.. I'm very appreciative for your tech support concerning this issue...

Anitoli
Knighted
Knighted
User avatar
Posts: 3352
Joined: 05 May 2013, 12:35
Location: Lewiston, Maine
Has Liked: 1736 times
Been liked: 1548 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby Anitoli » 31 May 2017, 06:16

That is a pretty good indicator that a tube or tubes are bad. You will be better served to just replace all of them with a matched set. Trying to piece meal together a set without being able to verify current draw/bias point is a crap shoot.

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 31 May 2017, 06:45

They are new.. I just installed a matched set of JJ's... After I installed them I still had the same problem.. It must be in the circuitry in one of the tubes is my guess... The amp had never given me any problems up till a month ago... I noticed all the tubes where leaning to one side.. I reseated them and it worked great... Then a few weeks ago.. I found the blown fuse.. Replaced it and used it for one rehearsal... Now I can only use the amp with the fuse in it one time.. Once I put it on standby.. It's toast... Fuse blows...... I'm going to reinstall the tubes again.. See if it fires up.. and retest the standby.. If the fuse blows... I'm left with no choice but to take it in... :scared2

Anitoli
Knighted
Knighted
User avatar
Posts: 3352
Joined: 05 May 2013, 12:35
Location: Lewiston, Maine
Has Liked: 1736 times
Been liked: 1548 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby Anitoli » 31 May 2017, 07:19

Current production tubes can fail at any time. Is the tube vendor local? Even if they are not talk to them Most of them will work with you if you just bought them and they are bad.

Also make sure the fuse you are replacing is a slo-blo type. A fast blo might not withstand the inrush current.

surfnorthwest
El Jefe
El Jefe
User avatar
Posts: 15577
Joined: 31 Jul 2007, 19:02
Location: Land of Hendrix
Has Liked: 3134 times
Been liked: 5053 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby surfnorthwest » 31 May 2017, 11:19

Rroxon wrote:They are new.. I just installed a matched set of JJ's... After I installed them I still had the same problem.. It must be in the circuitry in one of the tubes is my guess... The amp had never given me any problems up till a month ago... I noticed all the tubes where leaning to one side.. I reseated them and it worked great... Then a few weeks ago.. I found the blown fuse.. Replaced it and used it for one rehearsal... Now I can only use the amp with the fuse in it one time.. Once I put it on standby.. It's toast... Fuse blows...... I'm going to reinstall the tubes again.. See if it fires up.. and retest the standby.. If the fuse blows... I'm left with no choice but to take it in... :scared2



JJ's.... one of these days you guys will learn to keep that junk out of Marshalls.
My Gear
Surf's Jukebox

Image
'When I Don't Have Anything Interesting to Play, I just Play Fast'

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 31 May 2017, 17:03

Damn... Easy does it please.... This is the first time I've changed tubes.. Don't be a downer.. Just let me know what tubes are better.. You don't have to be a noob..... Just help if you can or go away........ Just maybe some of us just aren't as knowledgeable as you... You could at least recommend something other than be an *^%#&*()(*&^%$.. I'm trying to find out why the F1 fuse keep blowing... doubt the problem is a JJ tube.........

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 31 May 2017, 17:09

Anitoli wrote:Current production tubes can fail at any time. Is the tube vendor local? Even if they are not talk to them Most of them will work with you if you just bought them and they are bad.

Also make sure the fuse you are replacing is a slo-blo type. A fast blo might not withstand the inrush current.

I appreciate your help.. seems like I ruffled some feathers by mentioning JJ tubes... I've been on this site for a total of two days.. and you are the only one that has given me some ideas to help with my fuse problem.. I'll find a slo blo fuse.. It just may be the answer....

surfnorthwest
El Jefe
El Jefe
User avatar
Posts: 15577
Joined: 31 Jul 2007, 19:02
Location: Land of Hendrix
Has Liked: 3134 times
Been liked: 5053 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby surfnorthwest » 31 May 2017, 17:47

It is a inner joke on the forum, not directed at you so nothing personal.

For the JMD1 a good set of Mullard EL34RI tubes would be good.
My Gear
Surf's Jukebox

Image
'When I Don't Have Anything Interesting to Play, I just Play Fast'

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 02 Jun 2017, 07:36

Well I ordered some Slo Blo fuses, so I'm hoping that takes care of the problem.. I know that somewhere down the road I'll have to take the head in... I'll try the mullard EL's in the future, but for now I'm using what I have.. Thanks for the tube tip though.. I'll do some research on the Bias settings for them... We have some gigs coming up fast and I need everything in good working order.. Can't be worried about fuse's or tubes going out.... If I can't use my head I'm left with no other choice but to use my MG Practice combo ... Not happy about that... Thanks for your input... LOUD and PROUD my friends.............Peace..........

skinnyj
Diamond Member
Diamond Member
User avatar
Posts: 1129
Joined: 09 Jun 2013, 19:22
Location: Manchester, NH (aka Northern MA)
Has Liked: 409 times
Been liked: 614 times

Re: jmd 1 head fuse keeps blowing

Postby skinnyj » 02 Jun 2017, 08:05

Rroxon wrote:Damn... Easy does it please.... This is the first time I've changed tubes.. Don't be a downer.. Just let me know what tubes are better.. You don't have to be a noob..... Just help if you can or go away........ Just maybe some of us just aren't as knowledgeable as you... You could at least recommend something other than be an *^%#&*()(*&^%$.. I'm trying to find out why the F1 fuse keep blowing... doubt the problem is a JJ tube.........


Stick around here long enough and you will see that Surf isn't exactly enamored with the JJ brand. His comments were not directed at you, personally. Like he said, it's a running joke here. :Cheers

Someone should repost Surf's "JJ Tube 'Shootout'"... :bgrin
'84 Marshall JCM800 4104
Blackstar HT-20
Marshall Class 5
ADA MP-1 (Version 1)
Line6 AX-212 (and I'm NOT ashamed)
1987 Les Paul Standard
2009 American Standard Strat
2015 PRS SE Torero
Takamine EG531SC Acoustic

My Band: Fistful of Karma

Anitoli
Knighted
Knighted
User avatar
Posts: 3352
Joined: 05 May 2013, 12:35
Location: Lewiston, Maine
Has Liked: 1736 times
Been liked: 1548 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby Anitoli » 02 Jun 2017, 08:22

Exactly. The first few times i used this forum every time i typed JJ it changed to "shit". Not being in the know i was scratching my head. :bgrin

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 06 Jun 2017, 23:05

Well .. I installed the 1 amp slo blo fuse, and now the amp seems to be working fine.. Even with Shit tubes........ There.. How do ya like me now ?? I thought about buying the Mallards.. But everyone would think I was talking about a fking duck.............

Anitoli
Knighted
Knighted
User avatar
Posts: 3352
Joined: 05 May 2013, 12:35
Location: Lewiston, Maine
Has Liked: 1736 times
Been liked: 1548 times
Contact:

Re: jmd 1 head fuse keeps blowing

Postby Anitoli » 07 Jun 2017, 02:56

Cool you got it working again. Unless it's specifically specified fuses in amps are always slowblo types.

Rroxon
<25
<25
Posts: 18
Joined: 25 May 2017, 19:25

Re: jmd 1 head fuse keeps blowing

Postby Rroxon » 09 Jun 2017, 18:31

I had the amp 5 years before I had any issues.. Why now it decided to blow fuse's .. Is beyond me ............. I haven't gigged with it yet, but we have a few coming up... I'd like to take it out in the back yard and crank the fucker, just because.... Never had it passed 4......... What I'd give to give some of my fucking neighbors strokes.................... ha .................. Rock and Roll will never die.... Neil Hey Hey......... OH WAIT... ASCAP, BMI will do their best to kill our gigs.........

:headbanger

Return to “Marshall JMD1”

Who is online

Users browsing this forum: No registered users and 1 guest