Fixing a Diamond X-500 2/70 antenna

[VK4GHZ]

Gerry, sorry I am not able to help.
The X-500 is on loan to somebody now, and I didn't take any pictures of the over all antenna.

From memory, (and that's becoming a worry!), the loading coils were towards the top of each section.
The three sections inside are identical and repeat one after the other.
If the match is poor like that, try the sections orientated the other way.

Unless someone else can give you a definitive answer?

[VK6ZFG]

Hi Adam

I have a X-500. I found it is poor in the mechanical department. I found it simply bends too much for a high gain antenna.

Took it down about a year back after being up for about 1 year from new. Found the seal at the bottom cracked. Intend beefing up the bottom section by an additional fibreglass sleeve or similar so as to make it stronger (hopefully without detuning it too much).

I will have a look at the insides and let you know how it goes together. If I don't come back to you in a few days send me a reminder.

Meanwhile try: http://www.xs4all.nl/~pa0fri/Ant/X510N/ ... cation.htm It is for the X510N so it might have the info you require.

73s

Igor

[VK6ZFG]

Diamond X500 Details

Measuring from the top of top section:

0 top of antenna wire, 2.5 OD
405 to top of 8t coil, 6.5 ID
455 to bottom of 8t coil, 6.5 ID
506 to top of capacitor assembly
557 to bottom of capacitor assembly
1007 to top of 8t coil, 6.5 ID
1047 to bottom of 8t coil, 6.5 ID
1142 to top of bottom section coupler, 9 OD

Measuring from the top of top mid section coupler:

0 top of coupler section, 9 OD
25 bottom of coupler section, 9 OD
340 top of coil 64t coupler, 8 OD
(actual 64t coil length, 8ID, between couplers 230)
670 top of coil 64t coupler, 8 OD
1049 to top of 8t coil, 6.5 ID
1090 to bottom of 8t coil, 6.5 ID
1285 to top of bottom section coupler, 9 OD

Measuring from the top of top bottom section coupler:

0 top of coupler section, 9 OD
25 bottom of coupler section, 9 OD
86 top of coil 64t coupler, 8 OD
(actual 64t coil length, 8ID, between couplers 230)
516 top of coil 64t coupler, 8 OD
918 to top of 8t coil, 6.5 ID
945 to bottom of 8t coil, 6.5 ID
1147 to top of bottom section coupler, 9 OD
Base coil assembly not measured

Notes:

I use silicon grease on the threaded joints to prevent then from seizing up (heats sink coupound).

The antenna is lacking in mechanical strength and bends under moderate wind conditions. It is defintely not suitable for areas where there are constant winds present. Constant recurring bending will result in fatigue failure of the fibgelass radome. The bending indroduces a loss in performance due to the radiation pattern skewing.

After about one years use the epoxy seal at the base was found to have failed allowing the fibreglass radome to be easily pulled out of the base assembly. The epoxy failure allows the entry of water. The antenna, as supplied, needs strenghtening if it is to be considered for long term service. I now use the shorter (lower gain) version and have had no problems. The intention is to one day strengthen the X500 and place it back in service. I would not accept an antenna built like the X500 for commercial service use due to its poor mechanical construction.

73 Igor
VK6ZFG

[HG5AZR]

Hi Igor!

1.Do you have schematic of Diamond X-500?
Your details is not clear to me.

2.How many capacitors are in X-500?
Only 2 capacitors on bottom or more?

Thanks
Zoli

[HG5AZR]

Hi!

I like to know that what is hole in white teflon on bottom of X-500.
On 9. picture I see also a small hole near coil.Why?What is funktion?
All X-500 has this hole?
My antenna has this hole and realised that hear on X-500 has also this hole or similar.

Thanks
Zoli

[PA3HMP]

Does someone have pictures of the rest of the internals of the X500 ?

I recently got an X500 from a fellow ham but have some doubts about what is inside the top and middle section.
especialy because the X510 has capicitors parralel in some sections and my X500 does not.

Mark

[VK2XSO]

Sorry. Unfortunately mine is back up the tower and not in a position for me to take it down and take some internal photos.

[PA3HMP]

This is a picture of the base of the X500 I have now

http://i46.tinypic.com/fwsn6e.jpg

[PA3HMP]

can someone tell me how many pF this capp assy should be ?



There are two of them in the top section but both meassure different so one of them must be broken.

[PA3HMP]

Diamond X500 Details

Measuring from the top of top section:

0 top of antenna wire, 2.5 OD
405 to top of 8t coil, 6.5 ID
455 to bottom of 8t coil, 6.5 ID
506 to top of capacitor assembly
557 to bottom of capacitor assembly
1007 to top of 8t coil, 6.5 ID
1047 to bottom of 8t coil, 6.5 ID
1142 to top of bottom section coupler, 9 OD

Notes:

I use silicon grease on the threaded joints to prevent then from seizing up (heats sink coupound).

The antenna is lacking in mechanical strength and bends under moderate wind conditions. It is defintely not suitable for areas where there are constant winds present. Constant recurring bending will result in fatigue failure of the fibgelass radome. The bending indroduces a loss in performance due to the radiation pattern skewing.

After about one years use the epoxy seal at the base was found to have failed allowing the fibreglass radome to be easily pulled out of the base assembly. The epoxy failure allows the entry of water. The antenna, as supplied, needs strenghtening if it is to be considered for long term service. I now use the shorter (lower gain) version and have had no problems. The intention is to one day strengthen the X500 and place it back in service. I would not accept an antenna built like the X500 for commercial service use due to its poor mechanical construction.

73 Igor
VK6ZFG

are those measurements in inches ? or cm ? or ??
because mine looks different

http://i50.tinypic.com/2sayudd.jpg
http://i46.tinypic.com/rw2ruw.jpg

Mark

[PY8ELO]

Great job Adam!!!
I am sure it will help many hams around the world!!!

Best 73,

Silva.

PY8ELO

[VK4HJI]

can someone tell me how many pF this capp assy should be ?



There are two of them in the top section but both meassure different so one of them must be broken.

That's not a capacitor, its just a brass joiner to join the elements together.

[HG5AZR]

Who compared Diamond X-500 to other diamond dual band antenna X-30,X-50,X-200,X-300,X-510,X-700?

I am not satisfied on 70cm. On 70cm band no difference between short and long diamond antenna?Longer antenna not better on 70cm?

Experience?

Thanks Zoli

[HG5AZR]

Is black colour screw original in X-500 at joint between middle and upper element?

Other screws is normal,Nickel.

Thanks
Zoli