Jump to content

Blue Hawaii Special Edition


pabbi1
 Share

Recommended Posts

Hi,

My BHSE is in the hands of an engineer, an expert, of my total confidence. All fuses are OK, all tubes are OK, but the voltage of V + (B +) is half as it should be, there is a defect in the unit. We urgently need the BHSE scheme, but especially the PSU scheme. Justin, please....

Link to comment
Share on other sites

Wow, you waited 27 whole minutes before complaining you hadn't heard back from Justin.  Have you emailed him or called him at his business number to ask him about your problem?  I'm not sure he hands out the schematic for his proprietary amp -- maybe he does or others have it -- but calm the fuck down and approach this like you would with any electronic product you have purchased.

  • Like 1
Link to comment
Share on other sites

Heeeeeeey, I did not complain. Justin is already aware of my problem and he even told me to look for an expert. I found him. Preliminary evaluations were performed and a problem was detected. But without the BHSE scheme it becomes very difficult to get a solution.

And yes.... I'm in total panic. BHSE is not a blender.

Link to comment
Share on other sites

The expert looking at the BHSE should be able to find the problem. Did he/she check unloaded vs loaded voltages, pre-reg and post-reg voltages, etc? If not, he/she is not an expert.

From 2 seconds of googling images it looks like the BHSE power supply is the original version power supply with BJT current source, or similar.

  • Like 1
Link to comment
Share on other sites

Scheme: 

make plans, especially in a devious way or with intent to do something illegal or wrong.
"he schemed to bring about the collapse of the government"
synonyms: plot, hatch a plot, conspire, intrigue, connive, maneuver, plan
"he schemed to bring about the collapse of the government"

 

Schematic: 

(in technical contexts) a schematic diagram, in particular of an electric or electronic circuit.

Link to comment
Share on other sites

3 hours ago, mypasswordis said:

The expert looking at the BHSE should be able to find the problem. Did he/she check unloaded vs loaded voltages, pre-reg and post-reg voltages, etc? If not, he/she is not an expert.

Was thinking the same thing.

  • Like 1
Link to comment
Share on other sites

8 hours ago, Ekstatikon said:

Heeeeeeey, I did not complain. Justin is already aware of my problem and he even told me to look for an expert. I found him. Preliminary evaluations were performed and a problem was detected. But without the BHSE scheme it becomes very difficult to get a solution.

And yes.... I'm in total panic. BHSE is not a blender.

If Justin is already aware of your problem, how did he become aware of it...?

Use the same method to contact him for a schematic....   zimple..!

Link to comment
Share on other sites

The first BHSE's did use A1968's in the PSU but I hope Justin stopped that a while ago.  ;)  Any PSU issue with this design, check the pass fets but any "engineer" should have figured that out on his own.  Seriously, troubleshooting PSU is the really easy bit. 

Link to comment
Share on other sites

12 hours ago, kevin gilmore said:

sounds like a shorted zener

also easy to fix

this is probably correct. it's most likely the zener or the FET on the heatsink by the zener. Thats really about all the problem could be, from what I have seen, unless any burned resistors are spotted.

Link to comment
Share on other sites

  • 1 year later...

Hi all,

Just joined the BHSE club acquiring a nice early specimen with the serial number #34 :)

After some research here and on head-fi started to look for a set of good tubes.

Here comes a question: There is a big variation in plate current in the EL34 kingdom from specimen to specimen. Since the output tubes are current sourced and sinked, is there a risk of burning the source/sink with a tube with a high plate current?

For example Groove Tubes labels their EL34M according to their hardness parameter from 1 to 10 with the highest numbers being the most linear but as far as I understand drawing the most plate current. I'm looking for them (was advised the 7-9 range) but started wondering if too strong a tube can possibly burn its current source/sink?

Thank you in advance for any input!

 

 

 

Link to comment
Share on other sites

Hahaha :D

It's their way of quantifying when the tube starts to distort.

This is what Brent Jessee says: "The hardness is actually the plate current draw of the tube when under full operating voltages for the plate, screen grid, and with negative grid bias applied at the proper voltage"

What plate current correspond to their "hardness" they however do not disclose as its their commercial secret. Only the higher the "hardness" the higher the plate current. The Shuguangs I inherited my BHSE with were rated 30mA but unfortunately gave up the ghost.

PS Impressively made amp, Justin! Great job!

 

Link to comment
Share on other sites

Hi guys,

Sorry if this has been asked already: I rebiased a set of new tubes as per Justins instructions in a 4h session. Then after powering the amp again after few days the gain drifted away again to -27V and stays there unless I rebias again. Is that normal? I guess I dont need to rebias everytime I power it up?

Another Q: Are the 2A and 0,2A fuses fast or slow blow? I wanted to try some nice silver ones.

 

Thanks in advance!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.