It is currently Mon Mar 16, 2020 4:13 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 249 posts ]  Go to page Previous  1 ... 3, 4, 5, 6, 7, 8, 9 ... 17  Next
Go to page Previous  1 ... 3, 4, 5, 6, 7, 8, 9 ... 17  Next
Author Message
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 7:45 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Looks killer bluesky636, good job!

Can't wait to hear your take on how it sounds. :D

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 8:25 am
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
Thanks, shimmilou.

I just got out of bed and have to feed my two Goldens. If its not too icy out (snowed some last night) I'll take them for a walk and then get back at it and fire the amp up. Keep your fingers crossed. :D

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 8:39 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Better wear golf shoes, it's slicker than snot here, freezing rain then wet sleet that froze on windshield, then sleet. I had to drive through it all. :!:

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 9:05 am
Offline
Roadie
Roadie
User avatar

Joined: Tue Jun 28, 2011 11:54 am
Posts: 271
Location: Baytown, TX
Good luck! I don't think you'll need it, as it looks like a mighty fine assembly. It has been a pleasure following along your build. I check my emails hourly for updates to see if there is more to read on your build.

I don't mean to brag, but this 70 degree 100% humidity weather here in Southeast Texas is kinda ridiculous for January! It is an overcast sky, with misty rain though.

_________________
2000 American Deluxe Stratocaster
2011 Gibson Les Paul Trad Pro 50's
2007 Epi Les Paul Custom
90's ESP Eclipse
JH-1B Jimi Hendrix Crybaby
Analogman KOT
Korg Pitchblack
Boss NS-2 PH-2
Blues Deluxe Reissue
1999 & 2007 Marshall TSL 100 w/1960BV cab


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 10:44 am
Offline
Rock Star
Rock Star
User avatar

Joined: Tue Mar 01, 2011 3:10 pm
Posts: 5646
Location: Gateway to the West
Bill that is one sweet build. Curious that they followed the specs so close that the bell for the speaker had to be removed!

A bit OT...but do your Goldens like to play fetch with a tennis ball? My two will play for hours doing that.

Looking forward to that power switch going to "On" and seeing how much you like it. Awaiting that next post.

T2

_________________
-----------------------------------------------------------
What time is it? It's Fender Time.


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 10:51 am
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
shimmilou wrote:
Better wear golf shoes, it's slicker than snot here, freezing rain then wet sleet that froze on windshield, then sleet. I had to drive through it all. :!:


Just got back from our walk. I believe the meteorlogical term for the weather today is "blecch:. :lol:

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 10:53 am
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
BLUESMAN1904 wrote:
Good luck! I don't think you'll need it, as it looks like a mighty fine assembly. It has been a pleasure following along your build. I check my emails hourly for updates to see if there is more to read on your build.

I don't mean to brag, but this 70 degree 100% humidity weather here in Southeast Texas is kinda ridiculous for January! It is an overcast sky, with misty rain though.


All will be revealed soon.

I'm jealous. :lol:

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 11:03 am
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
T2Stratman wrote:
Bill that is one sweet build. Curious that they followed the specs so close that the bell for the speaker had to be removed!

A bit OT...but do your Goldens like to play fetch with a tennis ball? My two will play for hours doing that.

Looking forward to that power switch going to "On" and seeing how much you like it. Awaiting that next post.

T2


There were a few minor deviations (I think I mentioned them in my original post) that I returned to original spec.

Unfortunately, Annie, our 11 year old lost her companion of 7 years, Pete, this past March. It has been hard on all of us, especially her. She doesn't play with Lily, the 5 year old we adopted after we lost Pete, instead prefering to cuddle with my wife and I. Lily, on the other hand is a wild child. She loves to chase around the house with her toys and drag laundry and anything else she can find out into the back yard. :lol:

Pete
Image

Annie
Image

Lily
Image

Gonna go eat lunch now and then get to work. Stay tuned!

_________________
Bill

Image


Last edited by bluesky636 on Sat Nov 03, 2012 10:58 am, edited 1 time in total.

Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 2:27 pm
Offline
Rock Star
Rock Star
User avatar

Joined: Tue Mar 01, 2011 3:10 pm
Posts: 5646
Location: Gateway to the West
Fine looking Goldens there. Sorry to hear about losing Pete, we lost our first golden Jasmin about 9 years ago, she was 16 when we lost her and it is rough losing one. Our Two now are Bongo (looks alot like Pete) and we should have called him Mongo, he is huge 130lbs and he isn't fat, just really big. Our other Ginger is smaller and darker like you Lily. Will have to find some pics. Ok back on topic.

We are waiting for you to finish lunch and button up the rest of this amp build we await "Power On".

T2

_________________
-----------------------------------------------------------
What time is it? It's Fender Time.


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 2:55 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
It's 4:00 pm and things are not off to a good start.

Before installing the solid state rectifier, I plugged the amp in and quickly flipped the power switch to make sure that the power transformer did not blow up. All was ok.

Then I installed the rectifier and flipped the power switch again. Everything seemed ok, so then I flipped the standby switch to take some power supply measurements. There was a brief spark at the power supply cap that connects to point B on the schematic and I immeditately hit the standby and power switches.

Here is a link to the wiring diagram

https://taweber.powweb.com/store/5f6a_layout.jpg

and schematic

https://taweber.powweb.com/store/5f6a_schem.jpg

Here are the troubleshooting steps I have taken so far:

1. My AC line voltage input is 122.2 V.

2. I pulled the rectifier and measured the AC input voltage between pins 4 and ground and 6 and ground at the rectifier socket. Both measured 362 V AC. This seems about right. The vintage schematic shows 325 V AC between each terminal and ground with a 117 V AC input.

3. I had noted that the power supply caps provided in the current kit are physically larger than previously supplied so they are a tight fit on the mounting board. In fact, the plus and minus leads when bent to be soldered to the mounting board actually touch the individual cap's cases. I checked, and there is no short between the leads and the cases.

4. There are no shorts between each cap's positive lead and ground.

5. I measured and verified that the underboard wires that connect to points A, B, C, and D are present and that all other underboard wires are also present.

6. Between points A and B, I measure the choke resistance of 139 ohms.

7. Between points B and C, I measure the 4.7K ohm resistance of R25.

8. Between points C and D, I measure the 10K ohm resistance of R21.

9. I reinstalled the rectifier, plugged the amp back in and turned the main power switch on (but NOT the standby switch). I measured 472 V DC out of the rectifier at the input to the standby switch.

All other connections appear to be correct.

What have I missed? :cry:

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 3:30 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
OK.

I just plugged the rectifier back in and turned power on. All OK. Then I threw the standby switch. There was a much smaller spark at the cap and I watched as the open circuit plate voltage climbed on the two power tube sockets (I have my bias probe plugged in and set to monitor plate voltage). As the plate voltage climbed past 260 VDC I noticed a smell and slight wisp of smoke coming from the vicinity of the tube side on the V5 tube socket (closest to the rectifier). I flipped everything off immediately. I cannot see anything that was burning.

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 3:57 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
Ok. I touched up the solder joint on the cap connected to point B which eliminated the spark, but after a few seconds, the joint starts to make a "sizzling" sound. Could the cap be bad? Shorted internally or something?

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 5:04 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
Well, looks like I am done for the evening.

I decided to try installing my old tubes to see what would happen. I turned the power switch on and all the tube filaments lit up. I flipped the standby switch and the cap connected to B made a sizzling sound where the wire connects to the cap and the fuse blew. So clearly there is a short somewhere and I am guessing it is a problem with that cap as I can find no other wiring problems. I'm going to order a new set of power supply caps.

Does anyone else have any thoughts or suggestions? I'm kinda bummed out right now. :cry:

_________________
Bill

Image


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 8:16 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Have you tried with all tubes removed? That sizzling noise could be a loose connection, or the cap positive lead eyelet connection arcing on the can (the covering could have melted through, connecting the positive eyelet to the can from soldering). Even if an ohm meter shows no connection, it can still arc. If the cap were shorted, it would show with an ohm meter, and probably would have popped and blown open dramatically. Double check the polarity/connections on that cap board, and make sure that the can of the cap doesn't connect to the eyelet. :idea:

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: My Weber 5F6A Bassman Build-Up Thread
Posted: Sat Jan 21, 2012 10:17 pm
Offline
Rock Star
Rock Star

Joined: Mon Apr 05, 2010 2:37 pm
Posts: 8708
Location: Natural Bridge, Virginia
shimmilou wrote:
Have you tried with all tubes removed? That sizzling noise could be a loose connection, or the cap positive lead eyelet connection arcing on the can (the covering could have melted through, connecting the positive eyelet to the can from soldering). Even if an ohm meter shows no connection, it can still arc. If the cap were shorted, it would show with an ohm meter, and probably would have popped and blown open dramatically. Double check the polarity/connections on that cap board, and make sure that the can of the cap doesn't connect to the eyelet. :idea:


The problem initially occurred with the tubes removed. You could actually see the solder joint sizzle. The polarities are all correct.

But, I think you may be on to something. I have not pulled the capacitor board out yet, but I did look at the end of the cap closest to the eyelet with a bright light and magnifying glass. I could see what appears to be a tiny hole in the blue covering on the cap can right next to the eyelet and surrounded by solder flux. If that is the case, it would appear that the high voltage may be arcing over to the hole and running to ground through the can under the blue coating.

Rather than trying to remove the cap and insulate the end better, I just ordered some more caps from Weber. I ordered 8 caps even though I only need 4. Can't hurt to have a few spares. I'm going to just toss the ones I have now. I have an idea on how to mount them standing off the board slightly so that the cap can is not close to the eyelet. The problem is that the caps provided are 500 V instead of the 450 V that Weber used to provide. They are physically larger and difficult to fit on the mounting board. I specified 2-day or overnight shipping if possible on the web order form and told Weber I need the caps for this coming weekend. We'll see what happens.

_________________
Bill

Image


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 249 posts ]  Go to page Previous  1 ... 3, 4, 5, 6, 7, 8, 9 ... 17  Next
Go to page Previous  1 ... 3, 4, 5, 6, 7, 8, 9 ... 17  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: