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Miniature Power Relay

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Dan da man

New Member
I need to acquire a Hongfa jqx-105f-1 PCB relay. I can only find them sourced from China? Anyone know anywhere in the US I can buy one? Tried all the traditional spots like Digikey, Mouser, etc...

Also, I tested the existing relay and will post a video later. But when I applied 12v I got no reading on the switch posts...

First time poster so thanks in advance.

Dan F
Avondale PA



Active Member
Probably wont find Hongfa, I only get them off used boards in a pinch.

Try Omron G8P series or T&E /P&B T9A series or Panasonic JTN series.
These above are only in DC coil voltages, your relay is available in ac coils but you did not specify.

What is it out of?
You will need the entire # from the relay to do a proper match up, especially the coil, contact rating, form and insulation type.
A lot of the home appliances use the class F type

added: Did the relay click and you were measuring resistance at the contacts, yes?

G8P https://media.digikey.com/pdf/Data Sheets/Omron PDFs/G8P[1].pdf
T9A http://www.farnell.com/datasheets/2003846.pdf
JTN ttp://www.farnell.com/datasheets/1794180.pdf

jqx chart.jpg

Dan da man

New Member
1710268550692.jpg Sorry about the incomplete information this is for a treadmill motor control board. I removed the board and looked it over the only visual issue I could find was it looked like the relay sparked. I attached photos of the pins...


This pin looked damaged...

Compared to the other side...

full view




Dan da man

New Member
So I tested the relay again... I was too much in a hurry yesterday... and it seems to work fine. So I am going to re-install it and see if it works.
Last edited:


Active Member
What you describe and from what I see, is most likely the result of a bad solder joint on the board for that contact pin that is "sparked".

Sometimes it just needs to be resoldered and sometimes the whole relay pin just vaporizes from the arcing. Your pin looks fine, Just use some isopropanol to clean up the crudy bits.

Be aware that the ferule going thru the board might be destroyed. This can be important if they are using traces on both sides of the board as the resolder may not wick thru to the other side. If so, pre-tin the pad with a fine wire on the component side down thru the hole to the other pad .


Dan da man

New Member
Cleaned it up and re-soldered it on the board and it works like new... saved $265 for a new MCB.

Thanks for the input!



Well-Known Member
That is a common problem with these 'small' relays used on this kind of application, particularly with stove element controls etc.
What I do is beef up the foil around the pin by using copper wick used for desoldering purposes as a enhancement to the foil and beef up the current capacity.
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