Looking for an RF coil for Galaxy DX 2527 (RCI 2950)

[PoDuck]

I can do one better. Here's a picture, and it seems to be 3 1/2 turns of wire.



The plastic insulator is gone, there is no adjustable core, and that ferrite core that is there seems to only be being held in by some beeswax, because it will fall out if I have the radio upside down and key up. It will heat up pretty warm on TX. Not so warm you can't touch it, but warm enough to melt the wax.

I'm not sure that this is my only problem, or if it is really a problem at all, but since it is a part that is obviously not exactly up to spec, I figured I should replace it before spending too much time trying to troubleshoot other reasons I might only be able to get a 6 watt carrier.

 

[kaos513]

Pick the best that fits your radio below is a pic of my inventory we will need any techs help.Left to right 1,2,3,4

 

[PoDuck]

Well, I'm still waiting to hear back from R&R and Mike. I believe the core makes a difference on these things, so I hesitate to try putting in something else other than the OEM part until I have no other options. I could be wrong, and if so, someone can correct me.

 

[Dmans]

Looks to me that kaos513's #4 looks very similar. So similar that I wouldn't hesitate to try it with the original core.

73's
David

 

[kaos513]

send me pm PoDuck i can mail you out contestant no# 4 just pay shipping on it and its yours

 

[kaos513]

Check Your finals on the radio.

 

[PoDuck]

I will do that when I get back to the shop. I'm not sure what finals it uses, off the top of my head. They could be weak, given all the nonsense that I found in that radio. Power turned up to fifteen volts, final bias way off, about everything that could be turned needed adjustment.

 

[kaos513]

Maybe it just needs an alignment now.

 

[PoDuck]

Well, it's not taking to an alignment. I didn't have any of the finals or driver, so I ordered a handful of each. They should be here by the end of the week. The voltages at the finals are off, but they are high, not low. Since this is after the alignment, I think maybe the voltages are high because the alignment is trying to compensate for a weak TX section. I could be way off about that, but I would know already if I had finals in stock.

 

[kaos513]

If you have one of them transistor reader will show u if there good or not

 

[PoDuck]

I have one, but I try and put things on my bench as little as possible. I figured that if I'm going to pull them out, I'll do it when I have the part to replace it, just in case. That way I don't have to clear my bench, open the radio, etc. more than necessary. This is my radio, so nobody is on my ass to get it fixed, but if I keep pulling it out and putting it back on the shelf, that takes time away from fixing things for people that will be on my ass if I don't get their stuff fixed.

 

[PoDuck]

Okay, I have now screwed things up worse than they were. I get absolutely no output. I tested the driver and the finals, and all tested okay, so I just fully removed them, cleaned them, and applied new thermal compound, and replaced them, figuring I might as well, since I already had them desoldered. When I got things back together, now I get no output whatsoever. I screwed around with it for a while, and then I decided that I may have somehow messed something up, so I replaced all three power transistors, and still get nothing. I get no current reading across either TP1 and TP2 or TP2 and TP3 on the driver bias. I get collector voltage like I should, but I get no voltage at the base in transmit on Q48, and I get negative 1.2 volts on Q46 from the base, and zero volts on Q47 from the base when in TX. My guess is that it isn't the finals, and something else has gone whacky, but I'm not sure where to go next.

Anyone have any ideas?

 

[Dmans]

PoDuck,
I just re-read this post and noticed that the thread title has (RCI 2950) in the title.
Below are a couple pictures of my RCI 2950 parts radio-L34. This is an EPTZ295013Z board. It is already missing some components and has several burnt/repaired traces. It is nothing but a parts storage unit for me.

I will remove this coil and send to you for the shipping cost if it will help "prop up another soldier".

73's
David

 

[PoDuck]

Well, I'm not sure if I'll need it until I can get the damn thing working again. Once I do, I'll know if what I've done has worked or not. I'll let you know. Thanks.

 

[Handy Andy]

Ok, you'll need to look back at the schematic...

The coil goes ACROSS into the network, but TAPS from the Final Bias Feed - that means it was hooked up to the AM REGULATOR - I hope this is not what I think it is. And I hope you can probe (prove) me wrong...

Tap - test ohmic result from the Prong that goes to the Finals - to this tuning tank core. If it's open - you may have a blown trace of a component failure.

Check your schematic...


Remove that Mirror board, locate the AM regulator - the only thing you need to find is which Test point jumper side's - side the Mirror board conducts from (AM Regulator as being the Source) - if you break this down into blocks that is the next part upstream the AM Regulator.

This case? It's TP3... RED CIRCLED PART

(Read thru this first ok, then figure out your steps - for areas impacted are heavy current areas.)

Just turn on the radio on in AM mode - and the Negative lead of the DVM goes to a can, or any part that is FOIL GROUND - the other taps and checks for voltage amongst those 3 test points . Any of them that show 5 volts or so is your LEAD IN from the AM Regulator - the other two wouldn't have nay voltage or at least much of anything on them - because the AM Regulator is their source voltage.

If you don't have any voltage - you'll need to backprobe to the AM Regulator itself, to see if you have a blown trace. And then check Q51.

You also have a Bifilar winding - if it blew - it would prevent any RF going out.

Again check bottom foil traces for blown opens...or hopefully its a cold soldering joint you found out and just reheat it to reconnect.

When you have a problem with a coil like that other parts take a role - and this one retrieves power from the Bifilar too - means it will conduct the DC components up to C254 of the Final and Driver bias to it too...

So hopefully it's just a bad soldering joint and just needs to be reheated.
:+> Andy <+: