Helios 1r Stereo Type 69 Mic Pre/EQ - Replacement power adapter question

[skaren]

I'm looking for some advice if anyone could help!

I have two Helios 1r stereo preamp/eqs and one of them has stopped working. Measuring the voltage output from the power adapters on both units suggests that one of them is broken.

The power supply I need is "Switchin Power Supply 48v 0.3A". I cannot find the exakt replacement online.

Question 1: Would any adapter with this rating work for this purpose? Could it even have a higher amperage rating? It would need to be the same size to fit into the chassis but in theory would something like this work:https://www.amazon.co.uk/Replacement-Adaptor-Switching-SA-B083-SA-8083/dp/B07Y8MGM3T

Question 2: The 2 units differ slighlty in that the working unit has a capacitor(?) attached to the pcb where the power adapter wires are soldered in (as shown in picures 3 and 4). What's the purpose of this part and would you recommend that I install one when I find a suitable power adapter replacement?

Big thanks in advance!

 

[Whoops]

That capacitor is probably for extra filtering,
but it's clear by the photo that the capacitor is Bulged and it's damaged. You can see the damage in the top part of the cap and also by the burned color.
The PCB is also burned on the R6 and R1 resistors, so there was some over heating there.

Are you sure the problem is on the OEM Power adaptor and not in the PSU board?

 

[skaren]

That capacitor is probably for extra filtering,
but it's clear by the photo that the capacitor is Bulged and it's damaged. You can see the damage in the top part of the cap and also by the burned color.
The PCB is also burned on the R6 and R1 resistors, so there was some over heating there.

Are you sure the problem is on the OEM Power adaptor and not in the PSU board?

Thanks for your reply. Weirdly, the board that looks burned belongs to the unit that works.

The reason I think is that its the power adater is that there is a very small voltage mesasurement on the one I presume is broken whilst for the working one there's an overload reading.

I've ordered an adapter with the same rating and will try it out.

 

[Whoops]

Stramge for sure, But I would change without a doubt the Bulged Lytic capacitor and the 2 resistors (R1 and R6) even if that unit works, better safe than sorry.

Also you could try in the meanwhile take the Adapter of the Good unit and connect it to the bad unit to see if that makes it work, they you would be sure it's the adapter and not something else

 

[skaren]

Just to follow up, I installed this replacement adapter that I bought on ebay and the unit now works fine.

Thanks again for the suggestions.

 

[fullineproduction]

Thanks for your reply. Weirdly, the board that looks burned belongs to the unit that works.

The reason I think is that its the power adater is that there is a very small voltage mesasurement on the one I presume is broken whilst for the working one there's an overload reading.

I've ordered an adapter with the same rating and will try it out.

Hello

i lost one side (L) of my helios 1r
turns on for 1sec perfectly than goes out right side works perfectly

I just bought that same power supply that you said works the board of ch 1 looks perfect

did you have same issue just one side? I can light up the 48V on the (L) ch 1 though but mic pre lasts like 1/2 sec than goes out

thsnk u

 

[fullineproduction]

Hello

i lost one side (L) of my helios 1r
turns on for 1sec perfectly than goes out right side works perfectly

I just bought that same power supply that you said works the board of ch 1 looks perfect

did you have same issue just one side? I can light up the 48V on the (L) ch 1 though but mic pre lasts like 1/2 sec than goes out

thsnk u

 

[fullineproduction]

Hello

i lost one side (L) of my helios 1r
turns on for 1sec perfectly than goes out right side works perfectly

I just bought that same power supply that you said works the board of ch 1 looks perfect

did you have same issue just one side? I can light up the 48V on the (L) ch 1 though but mic pre lasts like 1/2 sec than goes out

thsnk u

Just to follow up, I installed this replacement adapter that I bought on ebay and the unit now works fine.

Thanks again for the suggestions.

Also my unit did not have that capacitor on it like yours do I need it?

What is the spec on that capacitor between the power supply leads?

I appreciate the help…. I could not find that original power supply anywhere I’m hoping that’s the issue…. I wish there was slack to plug in to he side that works to know for sure if it was that, but there is no slack on pinboard clips to flip ch 2 to ch 1

 

[fullineproduction]

I bought that same power supply you posted