OT: Quick GE Delta Question..

[kb0nly]

Is there a board that has some knowledgeable folks regarding the GE Delta? I will gladly post there if i can find one!

Otherwise a quick question for those that have dealt with the dark side of the commercial radio scene... lol

In the GE Delta i assume there is a jumper that prevents the radio from being programmed by the S-950/990 heads? I see mention of it on some websites that talk about the Delta, but none of them mention which jumper!

I got a pile of radios, half of them were 950's and the others seem to have been S550's. The ones that had 550's on them won't program with the S-950/990 heads, but the others will. If i pull the EEprom out of the 950/990 radios and put it in the 550's then the radio and head work together as long as i don't change the Mode which initiates a write to the radio. If i do that you hear some popping noises from the speaker than a long continuous tone and the radio has to be turned off and back on to make it work again on Mode 1.

I'm assuming the 550 radios were setup so that a control head can't write to them.

Thanks!!

[6V6GT]

Looks like P707 /J707 is the jumper you're looking for. It's located next to the X2212 eeprom on the TRS board.

Tim

[6V6GT]

I forgot to mention that the control cables are different for the "download" heads. They have an extra pair as I recall and it's necessary for the advanced heads to work properly.

' 73

Tim

[Jim202]

Forgot to mention that there is a GE Delta - Rangr group on Yahoo. Can't remember
the exact name, but it's there and has a number of active people on it.

Jim

[kb0nly]

Yep, all my cables are the 950/990 type, but i put a 550 head on one of them using one of those cables not knowing that difference at first. That's when i found out the radio worked with the 550 head but wouldn't allow programming with the 950/990 heads!

Thanks for the info on the jumper, i will give that a try tomorrow and see if that works on the others. I recall seeing that jumper next to the EEprom.

I will check into the yahoo group, a quick search of the groups should find it!

Thanks for all the help.

[ai4ui]

You may find that you like those Delta radios. Especially the SX model. With careful tweaking of the rx & tx VCOs it will operate from the bottom of the ham band well up into the Federal allocation with no noticeable loss of performance. There is a binary image firmware available for the 950/990 head that will make them front panel programmable for tx/rx & tone frequencies. When configured for 32 chs per mode it will scan all 32 of those channels if you want. The scan rate is very fast and the look back for the priority scan is fast as well, with minimal audio holes.

Service manuals, called LBI's, are available for downloading here:

http://www.repeater-builder.com/ge/lbi-master-list.html

Enjoy!

Robert

[kb0nly]

Thanks for the link! I will have to get those downloaded. I put the first one on the bench last night and tweaked the VCO's, works great in the ham band. I modified the heads already, that is slick, beats a Moto trunk mount for one reason, front panel programmable!

Not bad radios, i think i might be leaning towards the GE side of the fence for a while.

[kb0nly]

We are planning on using some of these as digipeaters for packet without a control head or cable, no problem making the connections inside as it has been well documented, but does anyone know how to have squelched audio output without a control head on these??

Trying to figure out how to duplicate the squelch control in the head or otherwise.

[Jim202]

If you can obtain a manual for the radios, there is a fixed squelch option. It only takes
a couple of jumpers to make it work. There should be a pot on the motherboard that
was put there for just this purpose. Most people don't use these radios in this fashion
though.

Jim

We are planning on using some of these as digipeaters for packet without a control head or cable, no problem making the connections inside as it has been well documented, but does anyone know how to have squelched audio output without a control head on these??

Trying to figure out how to duplicate the squelch control in the head or otherwise.

[kb0nly]

I got the manuals downloaded from RBTIP and found that. None of these radios had a trimpot in that location however, so i just soldered one in since i had some pcb mount trimpots that fit the holes perfectly, then i removed jumper J605 and i have squelch action!

I put a fixed value resistor between pin 7 and 8 to provide audio at pin 18, for some reason the discriminator audio at pin 7 on these Delta's isn't enough for a KPC TNC. Then i just adjust the audio level using R629 and all is well. I got one burning in as the digipeater right now.

So far so good!

[ai4ui]

GE Deltas are used extensively in Florida for the SEDAN network. See

http://www.commparts.com/pdfzips/ge_del ... _bauds.pdf for more information.

Regards

Robert

[kb0nly]

What are you guys seeing for receive sensitivity, the ones i have seen me to be half deaf at 144 and 145.

[ai4ui]

Spec - .25 uv or better. If it is a Delta S you have to tune the front end. If it's a Delta SX, I dunno.

Robert

[kb0nly]

It's a Delta S..

Working on the instructions for that now, problem is my radios dont match the drawings in that link with the .pdf file above.

I don't have L451.

[kb0nly]

I don't have C6 and C7 either...

[WB6NVH]

As far as cables go, there are over a dozen different ones. The non-downloading ones can be converted as the wires are still in the cable, just not connected to the plug end. There's a website out there which has this conversion info.

There are several GE groups on Yahoo - - there's a GE_Delta_Ranger group (note Ranger is mis-spelled) and also a regular GE group. Watch out for the original Delta-Ranger Yahoo group as it has apparently been abandoned by its creator/moderator and has an increasing amount of spam postings on it, as membership isn't supervised.

Although the 950 and 990 heads have their benefits on VHF and UHF, I do not like them on low band as they generate a lot of RFI. The 950 heads have no back-lighting and use a ridiculous "eyebrow" lamp shade option to illuminate the keys.

[ai4ui]

Scott

Did you look at this LBI?

http://www.repeater-builder.com/ge/lbi- ... 31516b.pdf

Robert

[kb0nly]

Ok, this is weird...

I downloaded that pdf file and printed out the page with the tuning instructions, my radios, which are all labeled as Delta's look nothing like them. I can't recognize anything and i have no idea what i should adjust now.

Got it hooked up on the bench, fired up the sig gen, and i removed the covers, and then i just sat there saying what the heck.

I don't have L451.

I don't have anything that looks like or is labeled, C1 through C7.

What is this radio then?

[kb0nly]

Yep, mine look nothing like that!

[ai4ui]

That would probably be a Delta SX. It doesn't have a tuned front end 'cause it is a wide band radio, as in wide freq seperation. There's not really a whole lot of tuning for those. You lock the VCO & go to it. I can't explain the poor reception. How were they on their original frequency?

[kb0nly]

Here is the radio with the shields in place...

http://www.kb0nly.net/Files/with.jpg

And here it is after i removed the shields trying to find something remotely the same, or even labeled the same as those instructions.

http://www.kb0nly.net/Files/without.jpg

[kb0nly]

Damn.. then i can scrap this project....

They worked great on 150 and up, ok at 146, but down around 144-145 they are deaf compared to everything else here. On the same antenna outside in place of my FT-2800 it only hears signals that are an S7 or greater on the 2800. It ignores anything less than that. Even with the squelch wide open they just arent there, it doesnt hear anything.

[ai4ui]

Yes, definately a SX. Looks like a late model one too 'cause of the black exterior. Can't explain the deafness.

[kb0nly]

I have a couple late models and the rest are the earlier gray models.

Well they are as deaf as a 90 year old in a glass box.

[Jim202]

The radio is an SX version with the pre-amp in the front end. Those can be tuned. You
just need to take some time to do it. I have never taken one down as low as your trying
to go. I would expect that the front end is rolling off way too fast to work with out
doing some slug playing.

Make sure you have the black square slug tuning tool. The gray colored ones are too
soft and will probably break off. I am surprised that you got the VCO to tune that
low without any mods.

Can't see what you have for a PA and you didn't show the side with the heat sink.
First off I would turn down the power out some before doing much playing. Bear in
mind that both the Delta-S and the Delta-SX will blow finals if pushed too hard. The
problem shows up as low output and a burnt up balance resistor at the PA transistors.
On a 100 watt radio I use to run them at about 60 watts.

Jim

I have a couple late models and the rest are the earlier gray models.

Well they are as deaf as a 90 year old in a glass box.

[kb0nly]

I have this radio running at 50w and the VCO just needed a small adjustment for transmit and receive. Getting that part done took a whole three minutes tops.

Do you have the tuning info for the SX? Need to know the procedure, i have an adjustment tool that fits these slugs, so not a problem there.