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# How?

• Choose appropriate guywire
• Calculate lengths
• Think about it
• Do it
• Regularly check it

## Choose appropriate guyrope

Big antennas and masts in permanent or temporary locations are part of the essential equipment for successful amateur radio stations. Their construction and installation needs a lot of time, effort and investment. Such installations are frequently exposed to many unfavourable conditions – static pressure and dynamic mechanical tensions, changes of temperature, humidity etc. These conditions, as well as the construction of the installation itself, can constitute a serious constructional problem in terms of working life, reliability, safety and avoidance of potential accidents.

A rigorous technical solution to all the design questions connected with the construction, securing & installation of such masts & antennas is complex. In order to calculate the answers, it is necessary to put material engineering, statics and dynamics of stressed constructions together. Radio amateurs frequently choose the most suitable solution according to their personal experience. Now in many cases, thanks to their common sense, all is well, but, nevertheless, they often start with incomplete knowledge of the parameters of materials and components being used which can lead to unnecessarily expensive “overenginneered” designs, or even inadequate design.

The Mastrant calculators help answer these questions and remove much of the guesswork. No two mast/antenna installations are identical, and the Mastrant calculators can make specific calculations for your individual installation’s guying requirements. After you fill in all the essential parameters, the Mastrant calculator will calculate the important numbers for you, and guide you as to which guying materials to choose so that the installed mast/antenna has guying which is both reliable and safe and is neither over or under engineered.

Unfortunately, the calculators cannot provide you with answers to every possible combination of mast/antenna. However, they can be used as guidance for any normal situation. The calculators will provide you with accurate & reliable results, but please remember “garbage in = garbage out”, so we suggest you carefully double check all your inputs.

You can choose the requested calculation from the menu on the left.

(If you are not overly familiar with Newtons, please remember 1 decca Newton (1daN) is almost the same as 1Kg.)

To see more details, please visit section Calculations.

## Calculate lengths

The calculator (section How-to, Calculations) will work out the lengths of guys necessary for guying your mast. It will calculate for guying in either three or four different directions and one to six levels of anchoring. It permits you to select the exact guy anchoring heights for your mast, and assumes that the ground is level.

Remember to include a surplus to cover any measuring inaccuracies and the thimble termination at either end. The calculator will show you the length of the guys needed for each level, and the total length required for the whole mast.

You can study the results and decide if you want every guy to be an unbroken length, or if you want to save money and have joints. Jointing shorter pieces obviously uses the odd lengths more economically, but please do not even think of tying a knot to make a joint, do it properly with the correct hardware, otherwise a large part of the guy strength will have been lost.

The calculator works out how many reels of guy you will need in total for whichever way you choose.

Use the “Forces in guywires” calculator to work out what strength guy you need, and then you are ready to order your new guys and accessories.

## Think about it

Basic instructions

## Do it

Recommended procedure

## Regularly check it

After final tensioning of the guys in "idle" the rope will for some time continue "settling". Check the guys and, if necessary, tension them the next day after the installation and then about 3 times at intervals of about 1 week. Then, it is very useful to check the guys after every windstorm or every 6 months.

## News

• ### Strength of P4 and P5 26. 4. 2018

We are updating the ratings for Breaking Strength and Safe Working Load for our most popular rope, 4mm and 5mm Mastrant-P. We began improving the construction of this rope in our production process more than 6 years ago and have been testing samples from each run. We are now satisfied that the changes have resulted in consistent, permanent improvements. Here are the new ratings:
Mastrant-P, 4 mm: BS=440 daN (about 440 kg, 970 lb.), SWL=132 daN (about 132 kg, 290 lb.)
Mastrant-P, 5 mm: BS=540 daN (about 540 kg, 1190 lb.), SWL=162 daN (about 162 kg, 360 lb.)

• ### Orders of customers from USA and Canada 6. 3. 2018

If you are considering placing an order and you want to save money on shipping, please place an order no later than March 11 in our on-line shop. You can pick it up in our booth 3607 at the Dayton Hamvention (choose “Personal pickup at fair”) or we will ship it directly to you from the US (choose “Dayton shipping”). Shipping from Dayton is free for orders over \$199 (to US), and shipping costs for smaller orders will reflect the cost of shipping from Ohio.

• ### Thread Rods 17. 11. 2017

We have added to our assortment (hardware section) very useful material for all who build their antennas yourself. It is stainless steel (AISI 316 - A4) thread rods 1 m long in sizes M5 to M12.