......
and I needed a smile.
😎
just imagine Flipper , bringing you Umbrella coctail ..... and you'll have another one

An externally hosted image should be here but it was not working when we last tested it.
Not sure they will help, but here's some more.
.........
crystal ball is more effective
give us 6x bigger pics
for that
OMG, i clicked it before realising it was Mr Fruta Flamingo de la Rosa singing (alguien canto)
Thanks, i needed a smile and ear plugs

Hi
I just realized that this thread is one year old!
Btw, I am on medical leave since I had a tooth surgery today. Keeping ice on my face as I browse. Otherwise, not bad, I took some days of medical leave and just started looking around for my toolbox...😉
I just realized that this thread is one year old!

Btw, I am on medical leave since I had a tooth surgery today. Keeping ice on my face as I browse. Otherwise, not bad, I took some days of medical leave and just started looking around for my toolbox...😉
As long as you have a prescription for good drugs and music, you will be Okie Dokie...
The E in tha SC
The E in tha SC
Not sure they will help, but here's some more.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Rob,
Can you re-post some close-up pictures? The devil is in the detail

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Here goes...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
everything seems fine ( at least to my tired eyes ) , except awful soldering ;
you probably fried that poor mosfet .... or you have short between that isolated wire and one underneath
you probably fried that poor mosfet .... or you have short between that isolated wire and one underneath
Hi guys,
Just a few quick question on the raw power supply of the original delite including the lux version,
1) will it somehow damage the Jfet (SJDP120R085) in a long run due to on/off surge voltage/ current that occurs? A ZenV9 alike circuitry (replacement of the light bulbs with the supply filter and the constant current source.) helps in this scenario?
2) Will it be worse for the Jfet if one is to install a delay turn on relay circuit at the speaker output?
Reason for the above questions is that the Jfet (SJDP120R085) ( seems to be pretty venerable, burns out too easily although heatsink and stablised voltage is within acceptable range (< 85vdc & < 65degC). Upon startup, a few seconds surge @ 79V at output capacitor is seen too.
Just a few quick question on the raw power supply of the original delite including the lux version,
1) will it somehow damage the Jfet (SJDP120R085) in a long run due to on/off surge voltage/ current that occurs? A ZenV9 alike circuitry (replacement of the light bulbs with the supply filter and the constant current source.) helps in this scenario?
2) Will it be worse for the Jfet if one is to install a delay turn on relay circuit at the speaker output?
Reason for the above questions is that the Jfet (SJDP120R085) ( seems to be pretty venerable, burns out too easily although heatsink and stablised voltage is within acceptable range (< 85vdc & < 65degC). Upon startup, a few seconds surge @ 79V at output capacitor is seen too.
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Hmm... I have a question related to the power supply also.
After filtering with some 20,000 uF of capacitance in a CRCRCRC configuration, I still had some hum, well, considerable hum. A lot of people here have thrown more capacitance at the problem, and Papa recommends a minimum of 25,000 uF. But since, I didn't have any more 5,000 uF, 200V caps on hand, I tried the cap multiplier by breaking up the above filter.
I used the third cap (from CRCRCRC) of 5,000 uF in the cap multiplier. The output of the cap multiplier then went through some additional filtering of 5,000 uF before going to the bulbs.
I still have almost the same amount of hum. What gives?
I'm using the 100V supply, bias at 2.2 A.
Thanks!
After filtering with some 20,000 uF of capacitance in a CRCRCRC configuration, I still had some hum, well, considerable hum. A lot of people here have thrown more capacitance at the problem, and Papa recommends a minimum of 25,000 uF. But since, I didn't have any more 5,000 uF, 200V caps on hand, I tried the cap multiplier by breaking up the above filter.
I used the third cap (from CRCRCRC) of 5,000 uF in the cap multiplier. The output of the cap multiplier then went through some additional filtering of 5,000 uF before going to the bulbs.
I still have almost the same amount of hum. What gives?
I'm using the 100V supply, bias at 2.2 A.
Thanks!
schematic + picture are worth zillion words ;
Alzheimer is doing his own - dunno where my crystal ball is

Alzheimer is doing his own - dunno where my crystal ball is

Hi guys,
Just a few quick question on the raw power supply of the original delite including the lux version,
1) will it somehow damage the Jfet (SJDP120R085) in a long run due to on/off surge voltage/ current that occurs? A ZenV9 alike circuitry (replacement of the light bulbs with the supply filter and the constant current source.) helps in this scenario?
2) Will it be worse for the Jfet if one is to install a delay turn on relay circuit at the speaker output?
Reason for the above questions is that the Jfet (SJDP120R085) ( seems to be pretty venerable, burns out too easily although heatsink and stablised voltage is within acceptable range (< 85vdc & < 65degC). Upon startup, a few seconds surge @ 79V at output capacitor is seen too.
1. if it's made by Papa's own novel circuit schm , do not worry
2. feel free to make anti click circ , but use two position relay - put 15R/1W resistor from "steady contact " of relay to gnd , so cap have current path for charging prior to speaker connection
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1. if it's made by Papa's own novel circuit schm , do not worry
2. feel free to make anti click circ , but use two position relay - put 15R/1W resistor from "steady contact " of relay to gnd , so cap have current path for charging prior to speaker connection
In regards to 1-I dont think Papa published specifically a schematic for that part. What worked for Tony did not work for me. Seems a fussy part for good sound.
Tony Wong has got this working, he has slow-start circuit I beleieve in his.
I dont know if he's lost any parts in his.
Yes, I am referring to Tony Wong's work.
The circuitry is similar to Fig 10 in Delite Article except for the R4, bias and voltage.
Bias - using 500W bulb, around 3.7A
Voltage - using 79Vdc
R4 - 2ohm
2 Ro85 jfet has being burnt so far ( only after playing, turning on/off many times). We are suspecting too high bias and surge during turn on. Anyone has any comments or precaution for us? However, base on what I understand on the SJDP120R085 datasheet, it seems that our operating conditions are fine or have I misunderstood it?
Thanks.
The circuitry is similar to Fig 10 in Delite Article except for the R4, bias and voltage.
Bias - using 500W bulb, around 3.7A
Voltage - using 79Vdc
R4 - 2ohm
2 Ro85 jfet has being burnt so far ( only after playing, turning on/off many times). We are suspecting too high bias and surge during turn on. Anyone has any comments or precaution for us? However, base on what I understand on the SJDP120R085 datasheet, it seems that our operating conditions are fine or have I misunderstood it?
Thanks.

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I forgot to mentioned that its a 110v bulb and failure occurs during startup without any changing of input leads.
My delite amp ,just completed with help of Tony
An externally hosted image should be here but it was not working when we last tested it.
I forgot to mentioned that its a 110v bulb and failure occurs during startup without any changing of input leads.
What value for C4?
Have you tested the R085's for Gate current?
How about using a Gate stopper at 100 ohms or so?
😎
Hmm... I have a question related to the power supply also.
After filtering with some 20,000 uF of capacitance in a CRCRCRC configuration, I still had some hum, well, considerable hum. A lot of people here have thrown more capacitance at the problem, and Papa recommends a minimum of 25,000 uF. But since, I didn't have any more 5,000 uF, 200V caps on hand, I tried the cap multiplier by breaking up the above filter.
I used the third cap (from CRCRCRC) of 5,000 uF in the cap multiplier. The output of the cap multiplier then went through some additional filtering of 5,000 uF before going to the bulbs.
I still have almost the same amount of hum. What gives?
I'm using the 100V supply, bias at 2.2 A.
Thanks!
Hi,
How is your ground set-up? Is it in a star ground configuration?
Eric
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