you seem to be the few ones to be active recently, this thread is old...
im facing the exact same problem.
could this polish relay work?
RM84-2022-35-1024 Relay electromagnetic DPST-NO Ucoil24VDC 8A/250VAC RELPOL | eBay
it says its a normally open DPST, not sure if its okay or not. Also, I'm assuming any relay could fit into the contact holes where it's soldered right?
Last edited:
Do you know if any relay will fit ?? in my case i will be buying a polish relay but im not sure if it will fit or not
RM84-3022-35-1012 Relay electromagnetic DPST-NO Ucoil12VDC 8A/250VAC RELPOL | eBay
Hi Estuera, just noticed your posts. I don't know your location so its hard to know what to suggest but that product will only suit if the contacts (not the coil) are rated for about 30VDC rather than by their AC rating. You can get an indication of fit from the number of visible pins and the dimensions of width and length but no guarantees unless the seller shows a drawing of its pin layout and overall dimensions. The seller of that pictured relay is also known to ask particularly high prices.
This Panasonic JW2SN-24V replacement part was recommended earlier in the thread and is also available in single quantity from Farnell and probably others: RS Components | Electronic and Electrical Components
This Panasonic JW2SN-24V replacement part was recommended earlier in the thread and is also available in single quantity from Farnell and probably others: RS Components | Electronic and Electrical Components
Im located in Canada, my local supplier has this one available,although it seems to be from a chinese brand or it may be generic, im kinda concerned that it is low quality and it may fail, which is why im looking into this Polish relay.
Also the original oem DEC relay has DEC 12VDC and 5A ratings, which is the same as the Polish one im looking for to buy. Arent we supposed to match the original ratings?
From the NAD 304 parts list, the original part spec. is TAIKO DGX2-24M which is a 24V coil version. There may well have been different types according to availability and cost, between following manufacturing runs. Cost minimisation is the name of the NAD game so I think we have to expect changes without notice and lots of them. NAD 304 - Manual - Stereo Integrated Amplifier - HiFi Engine
I would measure the voltage across the relay coil whilst it is activated to be sure that the supply is only about 12V under load before deciding that a 12V relay is correct in your example. I have seen 12V relays used with higher voltages too - seldom more than 20V though and that voltage doesn't need to be precise, since the relay will still close with a very low supply voltage and probably just runs hot with a high one. Note that there are usually 6 pins for the contacts in a DPDT arrangement so you'll likely need to trim 2 to make a DPST type that fits the PCB.
I'm curious that the original is a "sugar cube" format but can be substituted by a narrow type. What are the overall dimensions of the DEC relay? I have my doubts that it's an original part but perhaps the supply voltage was also changed when the relay was.
I would measure the voltage across the relay coil whilst it is activated to be sure that the supply is only about 12V under load before deciding that a 12V relay is correct in your example. I have seen 12V relays used with higher voltages too - seldom more than 20V though and that voltage doesn't need to be precise, since the relay will still close with a very low supply voltage and probably just runs hot with a high one. Note that there are usually 6 pins for the contacts in a DPDT arrangement so you'll likely need to trim 2 to make a DPST type that fits the PCB.
I'm curious that the original is a "sugar cube" format but can be substituted by a narrow type. What are the overall dimensions of the DEC relay? I have my doubts that it's an original part but perhaps the supply voltage was also changed when the relay was.
Last edited:
You're right, somehow I got mixed up when I searched up the part, it showed me the 12VDC variant, i have the 24VDC.
Anyways I stumbled upon this Japanese PDF file that contains the specifications of the DEC relay ,and luckily enough it has a drawing of it's measurements of the footprints and the relay overall. Not sure if all manufacturers include this kind of drawings but I'll have to look up.
If you know some relays that could potentially work let me know.
the original taiko dgx2-24m, by schematic and design is a 2P 1T
(two pole one throw or left&right single throw to engage)
or NO (normally open). so it's a 2-pins for coil power, and
4 pins for control.
you can take a 6-pin DPDT and cut off two pins (unless the
PCB has holes for it and NO electrical connections).
BUT no matter what you find and buy make sure the
physical pin dimensions (size, orientation, location, etc)
are identical to what you are replacing.
(you could pull the old, test it, and ensure the replacement
matches the old in operation and PCB fit).
I have the Panasonic jw2asn-dc24v as the 4-pin part
DPST same as the taiko. for my 304 refurb.
if you are looking for other vendors, look for 2 form A
and make sure the pins are the same function and size.
(two pole one throw or left&right single throw to engage)
or NO (normally open). so it's a 2-pins for coil power, and
4 pins for control.
you can take a 6-pin DPDT and cut off two pins (unless the
PCB has holes for it and NO electrical connections).
BUT no matter what you find and buy make sure the
physical pin dimensions (size, orientation, location, etc)
are identical to what you are replacing.
(you could pull the old, test it, and ensure the replacement
matches the old in operation and PCB fit).
I have the Panasonic jw2asn-dc24v as the 4-pin part
DPST same as the taiko. for my 304 refurb.
if you are looking for other vendors, look for 2 form A
and make sure the pins are the same function and size.
Previously, people have already doubled the rating of the original R333,4 resistors to 1W. This may have solved the immediate problem but is risky because it doesn't get to the heart of the problem of something working as per design for many years but then failing in many cases. Resistor ratings are usually important because they restrict current to safe limits and if that isn't sufficient protection, they can fail like a fuse before the more expensive or perhaps impossible to replace components downstream. So I suggest no more than 1W rating.
Fitting overkill resistors often ends in tears when a 5 cent part kills your $1000 amp. Metal film resistors are also tougher than carbon film and often glow red for some time before burning out. There is also greater risk is to your PCB charring and setting on fire there and it doesn't look pretty when the smoke clears. Leave some space between the resistors and board to ensure some air movement around them too.
Fitting overkill resistors often ends in tears when a 5 cent part kills your $1000 amp. Metal film resistors are also tougher than carbon film and often glow red for some time before burning out. There is also greater risk is to your PCB charring and setting on fire there and it doesn't look pretty when the smoke clears. Leave some space between the resistors and board to ensure some air movement around them too.
The original ratings for the resistors were 1/2 watt right? I think I'll go with the 1 watt resistors then, which one did you use?
Should I still use the metal film resistors with 5%? Or should I just go with the regular carbon composite resistors? They both have the same 5% tolerance.
Okay, so after getting all the parts, i replaced the relay with a new Relpol relay, and the R333 and R334 resistors with 1 watt resistors. But for some reason im still getting the same issue but its somewhat better sounding, one channel seems more clear than the other one. The R333 and R334 resistors also had their pads lifted and torn on one side, so i had to directly solder them to the next component in line.
I also replaced the R743 resistor which was burned, and the R742 which was blown.
Also when i replaced all the faulty components, i can turn on the amplifier, but the red-light lights up for about 3 seconds and then turns to green, and when i turn it off it goes back to red and it fades away after a few seconds.
Any ideas what i could do? I highly doubt it would be the capacitors since the amplifier sounded great after i bought it used until 1 month of usage which started showing these symptoms.
I also replaced the R743 resistor which was burned, and the R742 which was blown.
Also when i replaced all the faulty components, i can turn on the amplifier, but the red-light lights up for about 3 seconds and then turns to green, and when i turn it off it goes back to red and it fades away after a few seconds.
Any ideas what i could do? I highly doubt it would be the capacitors since the amplifier sounded great after i bought it used until 1 month of usage which started showing these symptoms.
Last edited:
3 months ago? I guess you must have been otherwise occupied.
I'd assume that the seller had the problem too, if as you say, there were lifted and torn tracks. It still may require new caps as they are normally only standard types in NAD product. The slow change of the status LED may also be due to one of the small caps used in the timing circuit of IC701 but for now, it does seems to work OK.
Some simple tests:
1. Remove all speaker and input leads, turn volume to min, power up and measure any DC voltage across the respective speaker (A) terminals for each channel. It should be less than 10mV but anything up to 30 or even 100mV is acceptable for this purpose. Don't adjust any setting controls yet.
2. Check the power supply voltages. Note this is a fancy class G type design which has 2 sets of power rails of nominally +/-35 and +/-56V for each amp. The higher supplies and a second set of power transistors switch in on demand for transient peak levels. There are going to be 2 sets of main power supply capacitors as well and you can simply read the voltages across these to check the associated rail voltages.
There is also a +/-26V (regulated) supply for the preamp and protection circuits that should be checked with a 'scope but a DMM should suffice for a simple check.
Let us know what you find, if anything.
Note before delving too far into this "PE" type design. It's not a straightforward amplifier by any means and there are many errors and false assumptions that can be made when trying to DIY repair them. There is a repair thread by suzyj here on a (IIRC) NAD3225PE, which is to a very similar design. I would link it but the 'net here is currently log-jammed.
I'd assume that the seller had the problem too, if as you say, there were lifted and torn tracks. It still may require new caps as they are normally only standard types in NAD product. The slow change of the status LED may also be due to one of the small caps used in the timing circuit of IC701 but for now, it does seems to work OK.
Some simple tests:
1. Remove all speaker and input leads, turn volume to min, power up and measure any DC voltage across the respective speaker (A) terminals for each channel. It should be less than 10mV but anything up to 30 or even 100mV is acceptable for this purpose. Don't adjust any setting controls yet.
2. Check the power supply voltages. Note this is a fancy class G type design which has 2 sets of power rails of nominally +/-35 and +/-56V for each amp. The higher supplies and a second set of power transistors switch in on demand for transient peak levels. There are going to be 2 sets of main power supply capacitors as well and you can simply read the voltages across these to check the associated rail voltages.
There is also a +/-26V (regulated) supply for the preamp and protection circuits that should be checked with a 'scope but a DMM should suffice for a simple check.
Let us know what you find, if anything.
Note before delving too far into this "PE" type design. It's not a straightforward amplifier by any means and there are many errors and false assumptions that can be made when trying to DIY repair them. There is a repair thread by suzyj here on a (IIRC) NAD3225PE, which is to a very similar design. I would link it but the 'net here is currently log-jammed.
A massive thanks guys, I replaced the relay on my 304 this evening and not only has it fixed the issue, I have low volume control like it used to be. Hugely Impressef with the help here. I registered today just express my gratitude. Ok thread revivals don't sit well with some but Kudos were it's deserved is my justification.
Hello, I am new here and came for a sound problem with my NAD304 amplifier. I am french, so sorry for my bad english.
Sometimes the sound disappeared, and appeared again when increasing the volume. This was actually due to the TAIKO DGX2-24M relay. I replaced it by the paasonic JW2ASN. It resolved this problem, but a hissing appeared on one output, especially when the amplifier is "hot"
Did anybody see this problem ? (I replaced the new relay by the old one and there is no hissing anymore)
Thank you for your aswers.
Vincent
Sometimes the sound disappeared, and appeared again when increasing the volume. This was actually due to the TAIKO DGX2-24M relay. I replaced it by the paasonic JW2ASN. It resolved this problem, but a hissing appeared on one output, especially when the amplifier is "hot"
Did anybody see this problem ? (I replaced the new relay by the old one and there is no hissing anymore)
Thank you for your aswers.
Vincent
Hiss is a different problem altogether and may be difficult to find without comprehensive testing.
Basic things are to try and determine where the problem lies, so is the hiss affected by the volume control, or does it matter what input is used. Have you operated all controls to make sure they all work smoothly.
Freezer spray dispensed very sparingly a drop at a time can be excellent for finding thermally defective components.
Basic things are to try and determine where the problem lies, so is the hiss affected by the volume control, or does it matter what input is used. Have you operated all controls to make sure they all work smoothly.
Freezer spray dispensed very sparingly a drop at a time can be excellent for finding thermally defective components.
thank you for reading me !
The problem does not depend from the source, since it appears without any device connected (just a speaker on the right output)
I am pretty sure it is due to mechanical conception of the Panasonic Relay.
I tested 2 Panasonic Relay, and also the genuine one.
During one of my test, the problem did not occur. But it appeared again after I moved my amplifier to put it on a shelf.
Actually, to be sure to have this annoying noise, I just have to do this:
- to connect a speaker on Right output
- turn on the amplifier
- increase the volume to a high level --> the noise appears and stay even if I set the volume to a lower level
The problem does not depend from the source, since it appears without any device connected (just a speaker on the right output)
I am pretty sure it is due to mechanical conception of the Panasonic Relay.
I tested 2 Panasonic Relay, and also the genuine one.
During one of my test, the problem did not occur. But it appeared again after I moved my amplifier to put it on a shelf.
Actually, to be sure to have this annoying noise, I just have to do this:
- to connect a speaker on Right output
- turn on the amplifier
- increase the volume to a high level --> the noise appears and stay even if I set the volume to a lower level
A problem with the relay wouldn't cause hiss.
Hiss is like white noise, like an FM radio between stations
That's electronic in nature, a mechanical contact won't do that.
I'm assuming you mean the hiss noise comes from the speaker and not from within the amp itself.
If you want to then you could add a link across the relay terminals to bypass it.
I would advise disconnecting the speaker before switching on and then connecting the speaker to the amp while the amp is already powered up.
That would stop any switch on thumps from the speaker.
Hiss is like white noise, like an FM radio between stations
That's electronic in nature, a mechanical contact won't do that. I'm assuming you mean the hiss noise comes from the speaker and not from within the amp itself.
If you want to then you could add a link across the relay terminals to bypass it.
I would advise disconnecting the speaker before switching on and then connecting the speaker to the amp while the amp is already powered up.
That would stop any switch on thumps from the speaker.
Well its possible that the old relay which you say was faulty... and what you described is a common fault... is not passing the very low level hiss.
That is the well known 'relay contact problem', you turn the volume up and it is OK because the higher current temporarily cleans the tarnished contact.
Your new relay is operating correctly and passing the really low level hiss through.
Does that make sense
The relay itself can not make the hiss. It is just a mechanical switch.
That is the well known 'relay contact problem', you turn the volume up and it is OK because the higher current temporarily cleans the tarnished contact.
Your new relay is operating correctly and passing the really low level hiss through.
Does that make sense
The relay itself can not make the hiss. It is just a mechanical switch.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.