Phono 3S Relay board revision and rebuild question

[David Roberts]

Having recently acquired a Phono 3S, with relay ‘issues’ (the repair of which necessitated the removal of the relay board), I am planning to revise the component placement before refitting the board, which should help to facilitate future repairs if required. This idea has been briefly discussed on a previous occasion on this forum, but I wanted to make sure that I have got the procedure right, and would like to hear from any member who may have already undertaken this mod’.

In order to preserve the correct pin connections, the relay must be reorientated, and fitted upside down in its new position on the visible side of the board. Am I correct in thinking that the two diodes need to be turned upside down as well, and does this also mean that the relay power supply wires need to be changed over (so that the switching is changed to the + line)?

Many thanks,

David

[bob orbell]

David, too have had issues with the relay and a diode and took a different approach, I will try and put pictures on, stay tuned, I stood the PCB away from the rear panel by 30mm on longer spacers, used Dip Sockets for the relays ( the greater distance now allows me to remove and replace the relays ) and 3mm brass rod soldered from PCB to Phono sockets, I also made all connections to rear of PCB, much neater. Bob

[colin.hepburn]

Hi David/Bob
I am also interested in this as I am about to replace the relay board in my CF pre amp with the newer version of the kit I got from Matthew and I also have spare relays for two older-styled single-sided relay board PCBs I have which I will use in other pre amp projects I have in mind to do so any helpful information on doing this is appreciated thanks
Colin

[Richard]

I may not be following the proposed re-location of the relays correctly... but, if they are located to the accessible side of the pcb, how will this help as you'd still need solder access to the other side to replace them?

The only issue with the designed build seems to be that the phono sockets are soldered to the pcb track "rings" and may have been soldered more than needed. The soldering only needs to be a couple of mm wide and can then be removed one by one with a sucker if needed later.

Another approach might be wire links between sockets and the pcb but generally if carefully constructed these relays and diodes are very reliable.

[bob orbell]

Please wait for the pictures, all will be so much clearer with visual. Bob

[David Roberts]

Hi Richard, Apologies, I should have been clearer. The intention is to use DIP/DIL sockets soldered to the visible side of the board, which is achievable with a steady hand and careful soldering. With all the components relocated, repair at any future stage should be easy. John Caswell suggested this in an earlier post on this forum, and I will try to find the link and repost it here.

[bob orbell]

I looked at that David \ all and my thoughts are that there will be very little holding the relays in place, IE, mechanical contact, one would just be relying on the copper tracks, that are only glued on, we all know how easily the tracks lift off and even with a dip sockets, the removal of the relay may pull the track off. Bob

[colin.hepburn]

Hi All
I have just been reconsidering this idea realizing that the relays now seem to be a discontinued item by most suppliers or are in low stocks or on eBay at a higher cost so I don’t see much point in doing it really now.

As I said in my post I got a new kit from Matthew and he kindly supplied me with the relays for my other two older single sides PCBs I have so three boards one to replace the one in the WD CF pre-one for a new project and one as spare so no real need for me too bother with the rebuild but would still like to see how you went about it, Bob.
Colin

[David Roberts]

I agree that the board is certainly fragile, and the solder pads surrounding the holes are particularly prone to popping off – especially when a suitably vigorous solder sucker is applied… However, the DIP/DIL sockets have 5 solder joints each side, which should help them to adhere to the pads, and the board. Once inserted in their sockets, the relays appear firmly located, but are easily removed by gently inserting a suitable lever between the relay and the socket, or using the correct tool for the job (if you have one).

The post by John that provoked me to think about revising the board before putting the whole thing back as per the original build instructions, is this one from March last year:

’’One of the main advantages of using the newer*relay*PCB is that as it is "Plated Through Holes" (PTH) you can mount the relays on the opposite side to that shown in the assembly notes to make it easier to remove them for faults and fault finding, and also put them in sockets.
One of a range of amplifiers I repair has the relays soldered to the PCB which takes about and hour to replace both. I fit sockets - result about 10-30 seconds to replace.
I know people are going to reckon that the sockets could be unreliable but once fitted, and held in with a tyrap the most unreliable thing is the*relay.’’

[bob orbell]

Pictures.