The 1983 Lipman Sport Wagon (part deux)

[djvanyel]

So after nearly having a heart attack from finding the old eagle nest was gone, I managed to find its new home thankfully.  Since my original thread on this car was lost due to a past catastrophe with the old site, I thought I'd start a new one here since I'm a week or two from finally getting this old blue bird back on the road (I hope).

After buying supplies for a full tune up and TFI upgrade, replacing the valve cover with an aluminum one, and many eBay purchases for assorted parts (shifter, hatch hinges, etc.) I'm hoping putting the final touches on her will be as painless as possible. On the other hand... She's been sitting since at least 2000 so I guess only time will tell.

Stay tuned.

[mudkicker715]

Calm the heart we relax here.

[IowaEagle]

Had to give you a thumbs up in finding us.  Be still thy heart (or take meds like me) but we are here and under old management, minus one.

[1985amceagle]

welcome back!

[vangremlin]

welcome back!

X 2

[djvanyel]

So despite the fact that "Big Blue" still isn't running well enough to drive around (she's missed all the New England snow this year!), I decided to take the plunge and buy one of my "most wanted" items for her: a stock AM/FM/CB. I believe the unit is complete and functional right down to the black plastic mic connector and DIN style faceplate bezel. If there's any demand for close-up shots of any aspect of the unit for reference or archival purposes, I would be happy to oblige before the unit goes into the dash.

[captspillane]

DO NOT INSTALL THE CB UNLESS YOU HAVE A MATCHING ANTENNAE.

A local gentleman bought a 1979 Spirit AMX new in 1979 and still has it. The factory replaced the CB radio three times under warranty. Each new one kept burning out. The cause of the problem was found to be a non-CB radio antennae. The CB radio needs to have one that is about 4" longer than the normal one or it will burn out the transmitting circuit. I have one Eagle that had a factory CB and measured the difference exactly but I can't find the number easily.

The actual minimum length number can be calculated by the height of the wave that corresponds to the lowest transmitting frequency. In other words it is okay if it is too long. It is only bad if it is too short. All AMC cars that started life without a CB radio also started life with one that is too short.

[carnuck]

Checking the match is the best way. It's not a length thing. Regular AM/FM antennas will throw a 3-1 or even higher match ratio which messes with the signal and forces it back into the radio. Kind of like how a microwave reacts when you put metal in it.

[djvanyel]

Well thanks to both of you for the warning... my knowledge of radio could probably be best characterized as: enough to get into trouble haha.

I believe this car may well have started life with the CB, since there is a mic holder on the dash and the existing stereo is clearly an aftermarket replacement (doesn't really fit the cutout) which I'm assuming it's probably dead as it had a ballpoint pen jammed into the cassette player when I bought the car. I've never powered it up so I'll consider it untested, but assumed dead. I'm also thinking the build sheets are likely hiding somewhere in the car, although I'm not going to bank on finding them to find out for sure what options she had from Kenosha.
Since this was a factory option, wouldn't the antenna size be standard across the years for the CB-equipped models? I could always measure the antenna since I have two different cars, one of which ('87 sedan) has a stock DIN style electronic head unit in it (not sure if it's original). If the antenna on the 87 and the 83 match, is it safe to assume they're the same (non-CB)?

Also, this, hypothetically, leads me to a follow-up question: it is possible to swap the antenna?

Perhaps I should open this to the broader forum since it's a definite good tip since these run upwards of $450 on the current market and they have many components made of unobtanium. Would love to hear your thoughts/input.

[djvanyel]

Ok, so I did some researching and fancy math and, correct me if I've got an error here but, I found that since the lowest frequency length comes out as ~11.12m, ideally a full-wave CB antenna should be ~33.377 feet long?! That translates to even a 1/4-wave antenna length of 8.344 feet, which is definitely shorter than the antenna on the car. However, I've seen notes a few places that suggest part of the car chassis acts as a ground plane for the antenna in mobile applications, therefore adding to the overall length.

Since the car doesn't yet live with me, I resorted to my photos of the car, and realized that it also had a CB mic stashed on the passenger side package tray when I first got it. I can't remember what the wires looked like under the dash, but I do know there aren't any extra holes in the car for an after-market antenna.

I also just made the painful realization that the chassis-side connectors for the speaker and power wiring were probably amputated and are probably long gone...   

But that aside, I'd love to know the correct length of the CB antenna. Probably a good figure to add into the eaglepedia since I'm sure there are a few people out there who wouldn't have known about the difference between the two.

[captspillane]

I found a note to myself saying the CB version is exactly 40 inches long. The regular wagon here at home that I measured just now is 32" long. If you unscrew the antennae part from the base the longer one screws in to the same base. Notice that the straight round shaft part is only 31" long but I included the hex part at the bottom but did not include the base. It is 32-3/4" from the top to the upper surface of the fender but only 32" of that is the removeable part that should be 40" for a CB radio.

[vangremlin]

I had an AMC AM/CB radio repaired by a member who hasn't been on the site lately.  Here are a couple tips he gave me, I have yet to install the AM/CB radio so I haven't followed his instructions yet.  There are directions in the Eagle TSM on how to do this procedure.

"...and if your going to use the cb don't forget to SWR the antenna system , If you need instructions ill copy the information from the Eagle service book you can also put the CB radio on a proper CB antenna."

"...by using a normal CB antenna it still will require to test and adjust for the lowest reading SWR the antenna, in which means that all of the power of the transmitter will go to the antenna and not back on the RF finals of the radio transmitter, Heat will cause transistors to Fail. Remember that 90% of the radios performance is in its antenna system so buy a good one like Wilson or K 40 ,SWR meters can be got at truck shops radio shack , and they do not cost a lot. "

Good luck!

[mudkicker715]

You do not want the lowest SWR but you want 1 SWR.

[carnuck]

1:1 is about the lowest you can get but less than 1.5:1 is useable.

[djvanyel]

So I finally remembered to take a tape measure to the antenna after doing some poking around under the dash earlier today... the antenna body is 31". Also, after looking very closely at the wires and the mic clip, it became obvious it was installed after market. So the prospect of having a functioning CB seems somewhat remote right now.

I've been contemplating finding a longer antenna, but if my understanding of the theory is correct, wouldn't I still need a significant length of lead to add to the length of the external antenna? The CB head I have included the original antenna splitter but that doesn't seem anywhere near long enough. Did the factory-equipped models have different antenna wiring or was it "plug and play" with the longer whip antenna?